Previous Article in Journal
The Use of PEEK Barriers in Bone Regeneration Procedures: A Scoping Review
Previous Article in Special Issue
Prevalence of Osteoporosis and Vitamin D Levels in Patients Undergoing Total Hip Arthroplasty: Insights from a Single-Center Experience in Italy
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Prosthesis
Volume 7
Issue 4
10.3390/prosthesis7040102
prosthesis-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Surgeon Learning Curve for Minimally Invasive Hemiarthroplasty Using the Direct Anterior Approach for Treatment of Femoral Neck Fractures in Elderly Patients

by
Francesco Maruccia
1,*,
Assad Assaker
2,
Massimiliano Copetti
3,
Serena Filoni
4,
Giacomo Trivellin
2,
Andrea Perna
1,
Franco Gorgoglione
1 and
Nicholas Elena
5
1
Department of Orthopedics and Trauma Surgery, Fondazione Casa Sollievo Della Sofferenza IRCCS, 71013 San Giovanni Rotondo, Italy
2
Department of Orthopedics and Trauma Surgery, Ospedale P. Pederzoli, 37019 Peschiera del Garda, Italy
3
Unit of Biostatistics, Fondazione IRCCS Casa Sollievo della Sofferenza Sofferenza IRCCS, 71013 San Giovanni Rotondo, Italy
4
Unit of Neuro-Rehabilitation, Fondazione Casa Sollievo Della Sofferenza IRCCS, 71013 San Giovanni Rotondo, Italy
5
Orthopedic and Traumatology Unit, Regional Center for Joint Replacement Revision Surgery, San Bortolo Hospital, 36100 Vicenza, Italy
*
Author to whom correspondence should be addressed.
Prosthesis 2025, 7(4), 102; https://doi.org/10.3390/prosthesis7040102
Submission received: 3 June 2025 / Revised: 4 August 2025 / Accepted: 12 August 2025 / Published: 20 August 2025
(This article belongs to the Special Issue State of Art in Hip, Knee and Shoulder Replacement (Volume 2))
Browse Figures
Review Reports Versions Notes

Abstract

Background: Femoral neck fractures (FNFs) are common injuries among the elderly and are a significant cause of morbidity and mortality. Hemiarthroplasty (HA) is the most suitable choice for elderly patients with multiple comorbidities and reduced functional demands. The direct anterior approach (DAA) to perform HA is widely used because, among other attractive features, it facilitates recovery of functional outcomes by limiting iatrogenic muscle damage. The learning curve for surgeons who perform minimally invasive HA using the DAA approach is unknown. The purpose of the study is to perform this determination. Methods: 850 patients (age: 82 ± 6 years) who had suffered FNFs were enrolled for the study between January 2017 and September 2022. The patients underwent minimally invasive hemiarthroplasty (using the anterior minimally invasive surgical (AMIS) technique) and DAA (AMIS + DAA). The patients were divided into three groups, one operated on by surgeons who have substantial experience in HA using DAA (Group A), another operated on by surgeons who have experience in adult hip arthroplasty (≥5 y) but had not specialized in using DAA (Group B), and surgeons who are being trained to perform adult hip arthroplasty (Group C). The metrics determined were duration of surgery, skin incision length, drop in hemoglobin level, length of hospital stay, complications experienced within 2 y of the procedure and the Harris Hip Score. For each of these metrics, the results were used to determine the learning curve for Groups B and C surgeons. Results: Using the learning curve profiles obtained, it was calculated that in order to achieve the competence of Group A surgeons, Group B and Group C surgeons need to perform 46 and 102 consecutive procedures, respectively. Conclusion: For an HA patient to achieve outcomes when treated for FNF using AMIS + DAA requires that the surgeon should have performed a large number of this procedure. In other words, the surgeon learning curve is modest for Group B surgeons but substantial for Group C surgeons.

1. Introduction

Femoral neck fractures (FNFs) are frequent injuries in the elderly and represent a major cause of morbidity and mortality [1,2]. Usually, non-displaced fractures (Garden types I and II) are managed with closed reduction and fixation using three cannulated screws [3], whereas fractures (Garden types III and IV) require hip replacement [4]. In most cases, hemiarthroplasty (HA) is used for older patients with comorbidities and low functional demands due to its benefits of early mobilization, shorter surgical time, and greater stability [5,6]. Conversely, total hip arthroplasty (THA) is preferred for high-demand patients aged 80 or younger with a life expectancy exceeding four years [5].
Different approaches are taken in HA surgery, among which are direct anterior, direct lateral, direct posterior, and anterolateral approaches [6,7,8,9,10,11,12,13,14,15,16,17,18]. The direct anterior approach (DAA), introduced by Smith–Peterson and modified by Heuter, utilizes intermuscular and internervous planes (sartorius-tensor fascia lata (TFL) superficially and rectus femoris-gluteus deeply) to access the anterior capsule [15]. The direct lateral approach starts with a longitudinal incision over the greater trochanter and partial splitting of the discal gluteus and minimus to expose the anterior capsule [11,12]. The direct posterior approach involves tenotomy of the short external rotators and piriformis at the greater trochanter to access the posterior joint capsule [10]. The anterolateral approach, introduced by Watson–Jones and modified by Rottinger [19,20], retracting the gluteus medius and minimus through the interval with the TFL to reveal the superior capsule. DAA is widely used because, among other aspects, it is thought to facilitate functional recovery due to the preservation of external rotators and use of natural planes [17]. At our institution, we routinely use DAA and a specialized table and fluoroscopy [16].
In the literature, there are randomized trials and cohort studies in which DAA has been compared to other approaches [7,8,18,21] and studies in which DAA and a minimally invasive technique (MIS + DAA) have been used [16,21,22]. However, a study in which the learning curve for surgeons who use MIS + DAA was determined is lacking. This is the purpose of the present study. In our study, HA was performed by three sets of surgeons (those who are very experienced in DAA, those who are experienced in HA but not specifically in DAA, and surgeons who are undergoing training in adult joint arthroplasty). The metrics determined were duration of surgery, skin incision length, decrease in patient hemoglobin level from pre-operation to post-operation, length of stay in hospital, complications, and Harris Hip Score.

2. Materials and Methods

2.1. Study Design and Database Constitution

This study represents a retrospective multicenter case series compiled in accordance with the CARE (CAse REports) guidelines [22]. All patients included in this analysis underwent uncemented bipolar HA for FNFs classified as Garden type III or IV. The patients were enrolled at the participating centers involved in the study between January 2017 and September 2022. In each procedure, the anterior minimally invasive surgery (AMIS) technique (Medacta Corporate International, Castel San Pietro, Switzerland) and the DAA approach were used (AMIS + DAA method). Collected variables were patient demographic data, experience level of surgeon with regard to DAA, skin incision length, duration of surgery, decrease in hemoglobin level pre- versus post-operation, post-operative complications, and Harris Hip Score (HHS) pre-operation and at 6 mo, 1 y, and 2 y post-operation.

2.2. Ethical Considerations

This study was validated by the Ethics Committee [15/CE/2024] conducted in accordance with the ethical principles outlined in the Declaration of Helsinki (1964 and subsequent revisions). Written informed consent for data use in research was obtained from all participants.

2.3. Inclusion and Exclusion Criteria

Inclusion criteria were as follows: age > 65 years, intact cognitive function, femoral neck fractures classified as 31-B1.3, 31-B2, or 31-B3 according to the AO/OTA system [23], and an American Society of Anesthesiologists (ASA) score ≤ 3 [24]. Exclusion criteria included severe obesity (Body Mass Index BMI)) ≥ 35 kg/m2), baseline hemoglobin < 10 g/dL, life expectancy < 2 months, or any condition (medical or cognitive) precluding participation in follow-up.

2.4. Surgeon Experience Classification

Surgeons were categorized according to the system proposed by Nakamura et al. [25]. Level 4 surgeons were senior surgeons who had substantial experience with DAA, having performed a great number of HAs using this method or having participated in academic studies focused on this method (herein, designated Group A surgeons). Level 3 surgeons are those who have extensive experience (≥5 years) with HA but have not specialized in DAA (herein, designated Group B surgeons). Level 2 surgeons are newly certified surgeons who were being trained to perform adult hip arthroplasty (herein, designated Study Group 3 surgeons).

2.5. Surgical Technique

Each patient underwent spinal anesthesia and received tranexamic acid (3 g total: 2 g IV, 1 g local). The patient was positioned supine on the AMIS traction table with the operative limb in the traction boot. An oblique incision (7–9 cm) was made 2–4 cm distal and lateral to the anterior superior iliac spine along the TFL. Blunt dissection through the subcutaneous fat was used to reduce the risk of lateral femoral cutaneous nerve (LFCN) injury, a known complication of this approach [8]. The interval between the TFL and sartorius muscles was identified and entered by incising the fascia over the medial TFL. Careful dissection avoided injury to the motor branch of the superior gluteal nerve and the femoral neurovascular bundle. Once the capsule was exposed, a self-retaining retractor was placed between the vastus lateralis and rectus femoris, and the ascending branch of the lateral femoral circumflex artery (LCFA) was isolated and clamped. The capsule was incised in a triangular fashion to allow femoral head removal after neck osteotomy, facilitated by external leg rotation. A Charnley retractor exposed the acetabulum. Capsular and ligamentous releases enabled up to 150–180° of external rotation, optimizing femoral elevation while minimizing risk to the acetabular rim. The femoral canal was broached sequentially until appropriate stem fit was achieved. Intraoperative fluoroscopy confirmed component positioning. Final components were implanted, the hip was reduced, and stability was assessed with external limb rotation. After layer-by-layer wound closure, drains were removed on post-operative day two. The patient was given acetaminophen (3 g/day) and ibuprofen (600 mg/day) for post-operative pain control. Mobilization began on post-operative day one, followed by a structured rehabilitation program in dedicated facilities for ~2 weeks.

2.6. Methodology for Determination of Learning Curve

Individual surgeons’ performances, in terms of surgery duration, length of hospital stay, incision length, and ΔHb, were graphically displayed as trajectories along the number of consecutive surgeries. The group-specific learning curve, for each outcome, was estimated and plotted using cubic spline interpolation. The number of consecutive procedures needed to reach Senior group-specific percentiles (75th, 80th, 85th, and 90th) estimated via root-finding numerical optimization for non-linear functions. The Senior group was chosen as the reference because naturally considered as the benchmark in terms of surgery performances. We investigated 75th, 80th, 85th, and 90th reached by the Senior group because they are considered robust high standards.

2.7. Statistical Analysis

Demographic parameters and clinical variables were reported as mean and standard deviation or median and range for continuous variables and as frequency and percentage for categorical variables. Groups’ comparisons were carried out using ANOVA models and the Pearson chi-squared test for continuous and categorical variables, respectively. Individual surgeons’ performances, in terms of surgery duration, length of hospital stay, incision length, and decrease in hemoglobin level (ΔHb), were analyzed using linear multilevel models nesting patients within individual surgeons using a compound symmetry matrix. Pairwise comparisons were derived using specific contrasts. Within this approach, we also investigated potential confounding effects of patient age and the side at which FNF was suffered (right side or left side).
Mortality at 6, 12, and 24 months was compared between groups using the Fisher exact test. A p-value of <0.05 was considered as statistically significant. All analyses were carried out using the statistical language R (Version 4.5.0).

3. Results

3.1. Study Population

A total of 850 patients who experienced FNFs and who received a HA and met all the inclusion criteria for the study were enrolled. The patient groups were matched for each of the characteristics of the patients (Table 1).

3.2. Surgeon Groups

Group A consisted of 90 patients treated by three surgeons (all male, aged 58, 55, and 47 years, respectively), classified as level 4 according to Nakamura et al. [25]. Each surgeon managed an equal number of patients. Group B included 280 cases treated by three surgeons (two males and one female, 56, 37, and 42 y.o., respectively) with substantial experience in hip surgery, although they routinely employed surgical approaches other than DAA classified as level 3. Group C comprised 480 patients evenly distributed among four additional surgeons (two males and two females, aged 31, 29, 32, and 29 years, respectively) who had no prior experience in hip surgery classified as level 2.

3.3. Duration of Surgery

The duration of surgery by Group A surgeons (mean: 45.8 min; range: 31–86 min) was significantly shorter than that for Group B surgeons (mean: 58.1 min; range: 37–121 min) and for Group C surgeons (mean: 70.0 min; range: 38–138 min) (Table 2). In order to achieve a duration of surgery corresponding to the 75th percentile time achieved by Group A surgeons (50 min), Group B and C surgeons would need to perform 36 and 96 consecutive procedures, respectively (Figure 1 and Table 3).

3.4. Skin Incision Length

The skin incision length made by Group A surgeons (mean: 10.1 cm; range: 8.6–12.1 cm) was significantly shorter than that made by Group B surgeons (mean: 12.4 cm; range: 8.9–20.4 cm) or Group C surgeons (mean: 15.0 cm; range: 8.9–25.2 cm) (Table 2). In order to achieve a skin incision length corresponding to the 75th percentile length achieved by Group A surgeons (10.7 cm), Group B and C surgeons would need to perform 46 and 102 consecutive procedures, respectively (Figure 2 and Table 3).

3.5. Blood Loss

Hemoglobin loss (Δ Hb) followed a similar trend. For patients operated by Group A surgeons, ΔHb (mean: 3.0 g/dL; range: 1.2–7.8 g/dL) was significantly smaller than for those operated on by Group B surgeons (mean: 3.4 g/dL; range: 2.1–7.5 g/dL) or Group C surgeons (mean: 3.9 g/dL; range: 2.1–7.2 g/dL) (Table 2). In order to achieve ΔHb corresponding to the 75th percentile loss experienced by patients operated on by Group A surgeons (3.5 g/dL), Group B and C surgeons would need to perform 13 and 75 consecutive procedures, respectively (Figure 3 and Table 3).

3.6. Length of Stay in Hospital

In order for to achieve patient length of stay in hospital to correspond to the 75th percentile value when Group A surgeons performed the surgery (5 days), Group B and C surgeons would need to perform 12 and 16 consecutive surgeries, respectively (Figure 4 and Table 3).

3.7. Complications

The most common comorbidities were recorded, with a similar distribution across the three groups: arterial hypertension, atrial fibrillation, osteoporosis, diabetes mellitus, and COPD. Types and frequencies of complications that presented within 24 mo post-operatively are given in Table 4. The most frequent complication was hematoma, but none of the patients required drainage. For a given complication, the fewest were experienced by patients who were operated on by Group A surgeons. Intraoperative fractures were also noted, with 1, 11, and 20 cases in Groups A, B, and C, respectively.

3.8. Harris Hip Score

Harris Hip Scores (HHSs) are presented in Table 5. At 6 mo following the procedure, HHS for patients who were operated on by Group A surgeons was significantly higher than that for those operated on by either Group B or Group C surgeons. The same trend was found at 1 y following the procedure. However, at 2 y following the procedure, the difference in HHS for patients in the three study groups was not significant.

4. Discussion

In recent years, DAA has gained increasing attention in the field of hip arthroplasty, particularly in the context of femoral neck fractures in elderly patients. Advocates of this approach emphasize its muscle-sparing characteristics, the potential for reduced post-operative pain, earlier mobilization, and shorter hospital stays. However, DAA is technically demanding and associated with a steep learning curve, especially when compared to other approaches such as the direct lateral or posterolateral approaches [26,27,28,29,30]. Although previous studies have analyzed the DAA learning curve in total hip arthroplasty (THA), evidence in the setting of hemiarthroplasty remains limited. To the best of our knowledge, no study has evaluated outcomes based on the surgeon’s level of prior experience with this specific approach in the context of hemiarthroplasty (HA). In this context, our study offers a unique contribution by directly comparing the learning curves of expert surgeons, surgeons with experience in alternative approaches, and novice surgeons, all performing cemented hemiarthroplasties via the DAA.
The most important finding of this investigation is the identification of substantial differences in the learning trajectories among the three groups. This study is the first to analyze and compare DAA-specific learning curves among surgeons of varying backgrounds. We chose an intuitive, simple, and clear method to estimate learning curves, different from others used in other studies (e.g., the cumulative summation method and the risk-adjusted cumulative summation method), because we were more interested in achieving certain high values than in detecting shifts. Previous research by Foissey et al. [26] focused on the learning curve of DAA in THA, distinguishing between senior and junior surgeons, but lacked a control group with DAA-specific expertise. Our data demonstrated that expert surgeons reached optimal intraoperative times (mean: 45.8 min, range: 31–86) significantly faster than those with other surgical backgrounds (Group B: 58.15 min, range: 37–121) or novices (Group C: 70 min, range: 38–138) (p < 0.01). Surgeons in Group B required 36 procedures to achieve operative durations comparable to those of Group A, while Group C surgeons needed 97. This threshold aligns with previous findings by Burnham et al. [27], who reported 40 procedures as the benchmark for significantly reducing complications following DAA-specific fellowship training. Precision in incision placement and length plays a crucial role in the success of DAA. Improper positioning can hinder exposure, especially of the proximal femur, and increase the risk of soft tissue damage. Bascom et al. [31] emphasized the importance of incision optimization to avoid maceration and facilitate surgical extension when needed. Our study supports these findings with the following: Expert surgeons (Group A) performed incisions with a mean length of 10.1 cm (range: 8.6–12.1 cm), significantly shorter than those by surgeons in Group B (mean: 12.4 cm, range: 8.9–20.4 cm) and Group C (mean: 15 cm, range: 8.9–25.2 cm) (p < 0.01). Achieving consistency of a 10.7 cm incision (corresponding to the 75th percentile of Group A) required 46 procedures for Group B and 102 for Group C, demonstrating the incremental improvement with experience. These results mirror those reported by Jin et al. [32], reinforcing the idea that incision control is a critical skill acquired over time. Intraoperative blood loss, as reflected by the decrease in hemoglobin levels, was significantly greater in less experienced groups. Group C showed a mean hemoglobin drop of 3.93 g/dL (range: 2.1–7.2 g/dL), compared to 3.0 g/dL (range: 1.2–7.8 g/dL) in Group A (p < 0.001). A loss of 3.5 g/dL marked the 75th percentile of Group A, a level achieved after 13 procedures by Group B, while Group C needed 75. This difference likely reflects longer exposure, less efficient hemostasis, and increased soft tissue handling during earlier procedures.
Length of stay (LOS) is a critical post-operative outcome in elderly patients. In our study, Group A achieved a 75th percentile LOS of five days, significantly lower than the 12 and 16 days seen in Groups B and C, respectively. Previous meta-analyses [33] have similarly demonstrated that DAA is associated with shorter LOS compared to the lateral and posterolateral approaches. This benefit likely stems from the muscle-sparing nature of the anterior access, which facilitates earlier mobilization and pain control. Functional recovery was assessed using the Harris Hip Score (HHS). At six months, patients operated on by expert surgeons demonstrated higher scores (mean: 80.36, range: 70.7–88.6) than those in Group B (mean: 79.23, range: 69.6–87.3) and Group C (mean: 77.84, range: 65.2–83.8) (p < 0.001). While these trends in differences were not seen at two-year follow-up, the early improvement is clinically significant, especially in this frail population. The anterior approach has been associated in the literature with a lower rate of complications and revisions compared to lateral and posterolateral techniques [33,34]. In our cohort, the most frequent complication was post-operative hematoma, occurring in 5 patients in Group A, 28 in Group B, and 61 in Group C. No patient required surgical drainage. Intraoperative fractures occurred in 1, 11, and 20 cases in Groups A, B, and C, respectively, findings that reinforce the correlation between surgeon experience and intraoperative safety. These results further reinforce the correlation between experience and intraoperative safety.
Despite the strengths of this study, including its substantial sample size and the stratification of surgeons by experience level, six study limitations are acknowledged. First, it is a retrospective study. Second, although the classification of surgeons into three distinct groups allowed a detailed comparison of learning curves, some heterogeneity in prior training and baseline technical skill may have influenced the outcomes independently of DAA-specific experience.
Third, the surgeons were not randomly assigned to cases, which could have introduced selection bias. Fourth, while operative time, blood loss, incision length, and functional scores were objectively measured, certain outcomes—such as patient-reported satisfaction or long-term prosthesis function—were not measured. Furthermore, although mortality data were recorded, a more detailed multivariate analysis adjusting for comorbidities, ASA class, and frailty scores would be needed to definitively attribute outcome differences to surgical performance. Fifth, the absence of a control arm using a different surgical approach (e.g., posterolateral or direct lateral) limits the ability to draw direct comparisons between DAA and other techniques. Sixth, despite statistical analyses resulting in good estimation processes, the different groups’ sample sizes (90 vs. 280 vs. 480) could still reserve a confounding effect. This doubt should be resolved by designing a new study with equal and large surgeon sizes for each group.

5. Conclusions

This study offers new insight into the learning curve and clinical outcomes of the direct anterior approach for cemented hemiarthroplasty, with particular emphasis on how surgical experience shapes operative efficiency, complication rates, and early recovery. Our findings demonstrate that experienced surgeons achieve significantly better intraoperative performance, reduced blood loss, and shorter hospital stays compared to their less experienced counterparts. Moreover, while early functional scores and complication rates are clearly influenced by surgical proficiency, long-term outcomes such as the Harris Hip Score and mortality tend to converge over time.
Importantly, we show that the number of cases required to achieve technical competence varies substantially depending on the surgeon’s experience, with novice surgeons requiring up to 96 procedures to reach benchmarks achieved by experienced surgeons in as few as 36. These findings underscore the technical challenges posed by DAA and the need for structured training pathways—potentially incorporating simulation-based education and mentorship programs—to safely integrate this approach into clinical practice. The direct anterior approach, when performed by adequately trained surgeons, appears to offer significant early benefits to patients without compromising long-term safety, positioning it as a valuable option in the surgical treatment of femoral neck fractures in the elderly.

Author Contributions

Conceptualization, F.M. and N.E.; methodology, F.M., M.C. and A.P.; software, M.C. and G.T.; validation, F.M., A.A., S.F. and F.G.; formal analysis, M.C. and S.F.; investigation, F.M. and A.P.; resources, A.A., S.F. and N.E.; data curation, F.G., F.M. and A.A.; writing—original draft preparation, F.M. and N.E.; writing—review and editing, A.P. and A.A.; visualization, M.C. and G.T.; supervision, F.G. and S.F.; project administration F.M. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

The study protocol was conducted in accordance with the ethical principles of the Declaration of Helsinki (1964) and its subsequent amendments. Following extensive consultation with the internal departmental Institutional Review Board (IRB) of Fondazione Casa Sollievo Della Sofferenza, IRCSS, and in consideration of the retrospective, non-interventional nature of this study, as well as the fact that all patients received treatment in accordance with the standard of care defined by our institution, formal ethical committee approval was deemed unnecessary.

Informed Consent Statement

Informed consent for the scientific use of anonymized clinical data was obtained in compliance with institutional regulations and the guidelines of the Italian Data Protection Authority. All patient data were fully anonymized to safeguard confidentiality.

Data Availability Statement

The datasets generated and/or analyzed during the current study are not publicly available due to institutional data protection policies but are available from the corresponding author upon reasonable request.

Acknowledgments

During the preparation of this manuscript, the authors used ChatGPT (OpenAI, GPT-4) for the purposes of language editing, specifically to review grammar and assist in the final stylistic and structural revisions of this manuscript. The authors have carefully reviewed and edited the output and take full responsibility for the content of this publication.

Conflicts of Interest

The authors declare no conflicts of interest.

Abbreviations

FNFsFemoral Neck Fractures
HAHemiarthroplasty
DAADirect Anterior Approach
AMISAnterior Minimally Invasive Surgery
THATotal Hip Arthroplasty
TFLTensor Fascia Lata
LoSLength of Stay in Hospital
HHSHarris Hip Score
ΔHbDecrease in Hemoglobin Level
SDStandard Deviation
ASAAmerican Society of Anesthesiologists
BMIBody Mass Index

References

  1. Spina, M.; Luppi, V.; Chiappi, J.; Bagnis, F.; Balsano, M. Direct anterior approach versus direct lateral approach in total hip arthroplasty and bipolar hemiarthroplasty for femoral neck fractures: A retrospective comparative study. Aging Clin. Exp. Res. 2021, 33, 1635–1644. [Google Scholar] [CrossRef]
  2. Kunkel, S.T.; Sabatino, M.J.; Kang, R.; Jevsevar, D.S.; Moschetti, W.E. A systematic review and meta-analysis of the direct anterior approach for hemiarthroplasty for femoral neck fracture. Eur. J. Orthop. Surg. Traumatol. 2018, 28, 217–232. [Google Scholar] [CrossRef]
  3. Mallon, Z.O.; Prentice, H.A.; Schlauch, A.M.; Fasig, B.H.; Paxton, E.W.; Sadeghi, C.; Okike, K. Femoral Neck System Compared with 3 Cannulated Screws in the Treatment of Femoral Neck Fracture in Patients Aged 60 and Older: A Multicenter Registry-Based Study. J. Bone Jt. Surg. Am. 2025, 107, 958–967. [Google Scholar] [CrossRef] [PubMed]
  4. Schneider, K.; Audigé, L.; Kuehnel, S.P.; Helmy, N. The direct anterior approach in hemiarthroplasty for displaced femoral neck fractures. Int. Orthop. 2012, 36, 1773–1781. [Google Scholar] [CrossRef]
  5. Lewis, D.P.; Wæver, D.; Thorninger, R.; Donnelly, W.J. Erratum to ‘Hemiarthroplasty Versus Total Hip Arthroplasty for the Management of Displaced Neck of Femur Fractures: A Systematic Review and Meta-Analysis’. J. Arthroplast. 2019, 34, 1837–1843. [Google Scholar] [CrossRef] [PubMed]
  6. Wang, F.; Zhang, H.; Zhang, Z.; Ma, C.; Feng, X. Comparison of bipolar hemiarthroplasty and total hip arthroplasty for displaced femoral neck fractures in the healthy elderly: A meta-analysis. BMC Musculoskelet Disord. 2015, 16, 229. [Google Scholar] [CrossRef] [PubMed]
  7. Saxer, F.; Studer, P.; Jakob, M.; Suhm, N.; Rosenthal, R.; Dell-Kuster, S.; Vach, W.; Bless, N. Minimally invasive anterior muscle-sparing versus a transgluteal approach for hemiarthroplasty in femoral neck fractures-a prospective randomised controlled trial including 190 elderly patients. BMC Geriatr. 2018, 18, 222. [Google Scholar] [CrossRef]
  8. Maccagnano, G.; Maruccia, F.; Rauseo, M.; Noia, G.; Coviello, M.; Laneve, A.; Quitadamo, A.P.; Trivellin, G.; Malavolta, M.; Pesce, V. Direct Anterior versus Lateral Approach for Femoral Neck Fracture: Role in COVID-19 Disease. J. Clin. Med. 2022, 11, 4785. [Google Scholar] [CrossRef]
  9. Petis, S.; Howard, J.L.; Lanting, B.L.; Vasarhelyi, E.M. Surgical approach in primary total hip arthroplasty: Anatomy, technique and clinical outcomes. Can. J. Surg. 2015, 58, 128–139. [Google Scholar] [CrossRef]
  10. Ait Mokhtar, M. Postero-posterolateral approach in total hip arthroplasty. Int. Orthop. 2020, 44, 2577–2585. [Google Scholar] [CrossRef]
  11. Hardinge, K. The Direct Lateral Approach To The Hip. J. Bone Jt. Surg. Br. Vol. 1982, 64, 17–19. [Google Scholar] [CrossRef]
  12. Solarino, G.; Moretti, L.; Vicenti, G.; Bizzoca, D.; Piazzolla, A.; Moretti, B. Hip hemiarthroplasty with modular neck: Is it useful in residents’ learning curve? A prospective clinical trial. HIP Int. 2020, 30, 30–36. [Google Scholar] [CrossRef]
  13. Graf, R.; Azizbaig Mohajer, M. The Stolzalpe technique: A modified Watson-Jones approach. Int. Orthop. 2007, 31, 21–24. [Google Scholar] [CrossRef]
  14. Chen, H.; Li, J.; Chang, Z.; Liang, X.; Tang, P. Treatment of femoral neck nonunion with a new fixation construct through the Watson-Jones approach. J. Orthop. Transl. 2019, 19, 126–132. [Google Scholar] [CrossRef]
  15. Meermans, G.; Konan, S.; Das, R.; Volpin, A.; Haddad, F.S. The direct anterior approach in total hip arthroplasty: A systematic review of the literature. Bone Jt. J. 2017, 99-B, 732–740. [Google Scholar] [CrossRef] [PubMed]
  16. Nogler, M.; Randelli, F.; Macheras, G.A.; Thaler, M. Hemiarthroplasty of the hip using the direct anterior approach. Oper. Orthop. Traumatol. 2021, 33, 304–317. [Google Scholar] [CrossRef] [PubMed] [PubMed Central]
  17. Wu, K.A.; Krez, A.N.; Anastasio, A.T. Direct anterior compared to posterior approach for hip hemiarthroplasty following femoral neck fractures. World J. Orthop. 2024, 15, 605–607. [Google Scholar] [CrossRef] [PubMed]
  18. Filippini, M.; Bortoli, M.; Montanari, A.; Pace, A.; Di Prinzio, L.; Lonardo, G.; Parisi, S.C.; Persiani, V.; De Cristofaro, R.; Sambri, A.; et al. Does Surgical Approach Influence Complication Rate of Hip Hemiarthroplasty for Femoral Neck Fractures? A Literature Review and Meta-Analysis. Medicina 2023, 59, 1220. [Google Scholar] [CrossRef]
  19. Hansen, B.J.; Hallows, R.K.; Kelley, S.S. The Rottinger approach for total hip arthroplasty: Technique and review of the literature. Curr. Rev. Musculoskelet Med. 2011, 4, 132–138. [Google Scholar] [CrossRef] [PubMed] [PubMed Central]
  20. Delanois, R.E.; Sultan, A.A.; Albayar, A.A.; Khlopas, A.; Gwam, C.U.; Sodhi, N.; Lamaj, S.; Newman, J.M.; Mont, M.A. The Röttinger approach for total hip arthroplasty: Technique, comparison to the direct lateral approach and review of literature. Ann. Transl. Med. 2017, 5, S31. [Google Scholar] [CrossRef] [PubMed] [PubMed Central]
  21. Gusho, C.; Hoskins, W.; Ghanem, E. A Comparison of Surgical Approaches for Hip Hemiarthroplasty Performed for the Treatment of Femoral Neck Fracture: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials. JBJS Rev. 2024, 12, e24.00067. [Google Scholar] [CrossRef]
  22. Gagnier, J.J.; Kienle, G.; Altman, D.G.; Moher, D.; Sox, H.; Riley, D. The CARE guidelines: Consensus-based clinical case reporting guideline development. Headache 2013, 53, 1541–1547. [Google Scholar] [CrossRef] [PubMed]
  23. Masionis, P.; Uvarovas, V.; Mazarevičius, G.; Popov, K.; Venckus, Š.; Baužys, K.; Porvaneckas, N. The reliability of a Garden, AO and simple II stage classifications for intracapsular hip fractures. Orthop. Traumatol. Surg. Res. 2019, 105, 29–33. [Google Scholar] [CrossRef] [PubMed]
  24. Horvath, B.; Kloesel, B.; Todd, M.M.; Cole, D.J.; Prielipp, R.C. Review of the ASA Physical Status Classification. Anesthesiology 2022, 135, 866–867. [Google Scholar] [CrossRef] [PubMed]
  25. Nakamura, T. Surgeons’ Level of Expertise. J. Wrist Surg. 2020, 9, 185. [Google Scholar] [CrossRef]
  26. Foissey, C.; Fauvernier, M.; Fary, C.; Servien, E.; Lustig, S.; Batailler, C. Total hip arthroplasty performed by direct anterior approach—Does experience influence the learning curve? SICOT-J 2020, 6, 15. [Google Scholar] [CrossRef]
  27. Burnham, R.R., Jr.; Kiernan, H.; Ortega, L.F.; Wesolowski, M.; Tauchen, A.; Russo, M.; Gerscovich, D.; Brown, N.M. Defining the Learning Curve of Anterior Total Hip Arthroplasty After Fellowship-specific Training. J. Am. Acad. Orthop. Surg. 2022, 30, e131–e138. [Google Scholar] [CrossRef]
  28. Wilson, M.D.; Dowsey, M.M.; Spelman, T.; Choong, P.F.M. Impact of surgical experience on outcomes in total joint arthroplasties. ANZ J. Surg. 2016, 86, 967–972. [Google Scholar] [CrossRef]
  29. York, P.J.; Logterman, S.L.; Hak, D.J.; Mavrogenis, A.; Mauffrey, C. Orthopaedic trauma surgeons and direct anterior total hip arthroplasty: Evaluation of learning curve at a level I academic institution. Eur. J. Orthop. Surg. Traumatol. 2017, 27, 421–424. [Google Scholar] [CrossRef]
  30. Carlet, A.; Buono, C.; Scaramuzzi, L.; Amendolagine, M.; Moretti, B.; Solarino, G. Efficacy of capsular repair in partial hip hemiarthroplasties: Outcome of 100 consecutive cases. J. Orthop. 2023, 15, 9–13. [Google Scholar]
  31. Bascom, N.; Levy, E.; Golden, T. Saddle to Incision Relationship: A Novel Approach to Localizing the Incision for Direct Anterior Hip Arthroplasty. Arthroplast. Today 2021, 10, 79–81. [Google Scholar] [CrossRef]
  32. Jin, Z.; Wang, L.; Qin, J.; Hu, H.; Wei, Q. Direct anterior approach versus posterolateral approach for total hip arthroplasty in the treatment of femoral neck fractures in elderly patients: A meta-analysis and systematic review. Ann. Med. 2023, 55, 1378–1392. [Google Scholar] [CrossRef] [PubMed] [PubMed Central]
  33. Bourget-Murray, J.; Horton, I.; Meniawy, S.E.; Papp, S.; Kim, P.R.; Grammatopoulos, G. The direct anterior approach is safe and shortens hospital length of stay following hemiarthroplasty for neck of femur fracture. Injury 2023, 54, 1186–1190. [Google Scholar] [CrossRef]
  34. Vasudevan, R.S.; Brzezinski, A.; Kaszuba, S.; Ani, L.; Essis, M.D.; Rubin, L.E. Direct anterior approach for femoral neck fractures: Why and how? J. Clin. Orthop. Trauma 2025, 67, 102995. [Google Scholar] [CrossRef]
Prosthesis 07 00102 g001
Figure 1. Individual surgeons’ trajectories of surgical time through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior0 surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Figure 1. Individual surgeons’ trajectories of surgical time through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior0 surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Prosthesis 07 00102 g001
Prosthesis 07 00102 g002
Figure 2. Individual surgeons’ trajectories of incision length through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation.
Figure 2. Individual surgeons’ trajectories of incision length through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation.
Prosthesis 07 00102 g002
Prosthesis 07 00102 g003
Figure 3. Individual surgeons’ trajectories of perioperative hemoglobin variation (Hb delta) through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Figure 3. Individual surgeons’ trajectories of perioperative hemoglobin variation (Hb delta) through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Prosthesis 07 00102 g003
Prosthesis 07 00102 g004
Figure 4. Individual surgeons’ trajectories of length of hospital stay through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Figure 4. Individual surgeons’ trajectories of length of hospital stay through the number of consecutive surgeries grouped by surgeons’ experience. The black curve is the group-specific learning curve estimated using a cubic spline interpolation. Shades of green indicate junior surgeons, while blue and purple shades represent medium-level surgeons, and yellow and red shades correspond to senior surgeons.
Prosthesis 07 00102 g004
Table 1. Characteristics of the patients in the three study groups.
Table 1. Characteristics of the patients in the three study groups.
CharacteristicsGroup AGroup BGroup Cp-Value
Number (n)90280480
Age, years, mean (SD)81.6 (5.48)81.7 (5.83)81.9 (6.23)0.896
Body mass index (kg/cm2)25.4 (3.90)25.4 (3.90)25.8 (4.36)0.706
Women, n (%)56 (62.2%)158 (56.4%)273 (56.9%)0.772
FNF on right side, n (%)36 (40.0%)147 (52.5%)255 (53.1%)0.068
Statistically significant data in bold (p < 0.05). SD: standard deviation.
Table 2. Summary of surgical and other parameters (mean, SD).
Table 2. Summary of surgical and other parameters (mean, SD).
CharacteristicsGroup AGroup BGroup Cp-ValueA vs. BA vs. CB vs. C
Surgical Time, min (SD)45.8 (8.20)58.15 (15.50)70 (19.66)0.00020.0061<0.0010.0026
Skin Incision length (cm)10.08 (0.83)12.37 (2.24)15.03 (3.27)<0.00010.005<0.00010.0008
Pre-Hb (g/dL)12.62 (0.94)12.57 (0.90)12.60 (0.91)0.8913
Post-Hb (g/dL)9.61 (1.08)9.19 (1.12)8.66 (1.11)0.00090.03770.00040.0033
ΔHb (g/dL) 3.01 (1.01)3.38 (0.80)3.93 (0.86)
LoS (day)3.94 (1.00)4.26 (1.21)4.63 (1.34)0.00060.04410.00030.0021
Statistically significant data in bold (p < 0.05). SD: standard deviation; Pre-Hb: pre-operative hemoglobin; Post-Hb: post-operative hemoglobin; ΔHb: hemoglobin loss; LoS: length of stay hospital. p-values derived for linear multilevel models.
Table 3. Values of parameters when surgery was performed by Group A surgeons and determined number of consecutive procedures needed to be performed by Group B and Group C surgeons to achieve the stated parameter value for Group A surgeons.
Table 3. Values of parameters when surgery was performed by Group A surgeons and determined number of consecutive procedures needed to be performed by Group B and Group C surgeons to achieve the stated parameter value for Group A surgeons.
OutcomePercentileGroup AGroup BGroup C
Duration of surgery (min)75th503697
80th513695
85th523587
90th542784
Skin incision length (cm)75th10.746102
80th10.846120
85th1145100
90th11.33897
ΔHb (g/dL)75th3.51375
80th3.8947
85th3.9947
90th4.235
LoS (day)75th51216
80th51216
85th51216
90th51216
SD: standard deviation; ΔHb: hemoglobin loss; LoS: length of stay in hospital.
Table 4. Types and frequencies of complications presented within 24 mo following the procedure.
Table 4. Types and frequencies of complications presented within 24 mo following the procedure.
ComplicationGroup AGroup BGroup C
Hematoma5 (71.4%)28 (63.6%)61 (64.9%)
Fracture1 (14.3%)11 (25.0%)20 (21.3%)
Infection0 (0.0%)2 (4.5%)5 (5.3%)
Dislocation1 (14.3%)3 (6.8%)8 (8.5%)
Table 5. The Harris Hip Score values (mean, SD).
Table 5. The Harris Hip Score values (mean, SD).
HHSGroup AGroup BGroup CTotalp-ValueA vs. BA vs. CB vs. C
HHS 6 mo80.36 (3.39)79.23 (2.80)77.84 (2.48)78.57 (2.83)<0.0010.00059<0.001<0.001
HHS 1 y81.82 (2.54)80.94 (2.55)80.02 (2.74)80.54 (2.72)<0.0010.02078<0.0010.00018
HHS 2 y81.14 (2.29)80.97 (2.19)81.22 (2.25)81.14 (2.29)0.540.5840.9610.361
Statistically significant data in bold (p < 0.05). SD: standard deviation; HHS: Harris hip score; HHS 6 m: Harris hip score at 6 months of follow-up; HHS 1 y: Harris hip score at 1 year of follow-up; HHS 2 y: Harris hip score at 2 years of follow-up.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Maruccia, F.; Assaker, A.; Copetti, M.; Filoni, S.; Trivellin, G.; Perna, A.; Gorgoglione, F.; Elena, N. Surgeon Learning Curve for Minimally Invasive Hemiarthroplasty Using the Direct Anterior Approach for Treatment of Femoral Neck Fractures in Elderly Patients. Prosthesis 2025, 7, 102. https://doi.org/10.3390/prosthesis7040102

AMA Style

Maruccia F, Assaker A, Copetti M, Filoni S, Trivellin G, Perna A, Gorgoglione F, Elena N. Surgeon Learning Curve for Minimally Invasive Hemiarthroplasty Using the Direct Anterior Approach for Treatment of Femoral Neck Fractures in Elderly Patients. Prosthesis. 2025; 7(4):102. https://doi.org/10.3390/prosthesis7040102

Chicago/Turabian Style

Maruccia, Francesco, Assad Assaker, Massimiliano Copetti, Serena Filoni, Giacomo Trivellin, Andrea Perna, Franco Gorgoglione, and Nicholas Elena. 2025. "Surgeon Learning Curve for Minimally Invasive Hemiarthroplasty Using the Direct Anterior Approach for Treatment of Femoral Neck Fractures in Elderly Patients" Prosthesis 7, no. 4: 102. https://doi.org/10.3390/prosthesis7040102

APA Style

Maruccia, F., Assaker, A., Copetti, M., Filoni, S., Trivellin, G., Perna, A., Gorgoglione, F., & Elena, N. (2025). Surgeon Learning Curve for Minimally Invasive Hemiarthroplasty Using the Direct Anterior Approach for Treatment of Femoral Neck Fractures in Elderly Patients. Prosthesis, 7(4), 102. https://doi.org/10.3390/prosthesis7040102

Article Metrics

Back to TopTop