Charcot-Marie-Tooth Disease of the Foot and Ankle: Imaging Features and Pathophysiology.

Charcot-Marie-Tooth disease (CMT) is the most common inherited peripheral polyneuropathy, resulting in length-dependent motor and sensory deficiencies. Asymmetric nerve involvement in the lower extremities creates a muscle imbalance, which manifests as a characteristic cavovarus deformity of the foot and ankle. This deformity is widely considered to be the most debilitating symptom of the disease, causing the patient to feel unstable and limiting mobility. Foot and ankle imaging in patients with CMT is critical for evaluation and treatment, as there is a wide range of phenotypic variation. Both radiography and weight-bearing CT should be used for assessment of this complex rotational deformity. Multimodality imaging including MRI and US is also important to help identify changes in the peripheral nerves, diagnose complications of abnormal alignment, and evaluate patients in the perioperative setting. The cavovarus foot is susceptible to distinctive pathologic conditions including soft-tissue calluses and ulceration, fractures of the fifth metatarsal, peroneal tendinopathy, and accelerated arthrosis of the tibiotalar joint. An externally applied brace can assist with balance and distribution of weight but may be appropriate for only a subset of patients. Many patients will require surgical correction, which may include soft-tissue releases, tendon transfers, osteotomies, and arthrodesis when necessary, with the goal of creating a more stable plantigrade foot. The authors focus on the cavovarus deformity of CMT. However, much of the information discussed may also be applied to a similar deformity that may result from idiopathic causes or other neuromuscular conditions. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

The Ischemic toe following forefoot surgery: A review of current practices and a proposed approach for management.

Toe hypoperfusion is a commonly encountered concern following forefoot surgery, yet there is limited clinical guidance available to surgeons to aid in management of this scenario. This work aims to review the etiology, pathophysiology and current strategies to address a perioperative ischemic toe. The authors review various interventions to approach this problem based on available evidence and clinical experience. Interventions to restore perfusion can be loosely based on the ischemic causality they intend to address. Described maneuvers to restore perfusion have, in turn, been designed to either chemically (through topical/local medication) or mechanically (bending/removing K-wires, adjusting repair tension) aid in mitigation of the offending cause. Depending upon the type of surgery performed, which may or may not include instrumentation, a surgeon can implement a series of steps to maximize restoration of toe perfusion. LEVEL OF EVIDENCE: V.

A quantitative analysis of hip capsular thickness.

PURPOSE: The purpose of this study was to provide a comprehensive quantitative analysis of capsular thickness adjacent to the acetabular rim in clinically relevant locations. METHODS: Dissections were performed and hip capsular measurements were recorded on 13 non-paired, fresh-frozen cadaveric hemi-pelvises using a coordinate measuring device. Measurements were taken for each clock-face position at 0, 5, 10 and 15 mm distances from the labral edge. RESULTS: The capsule was consistently thickest at 2 o'clock for each interval from the labrum with a maximum thickness of 8.3 at 10 mm [95 % CI 6.8, 9.8] and 15 mm [95 % CI 6.8, 9.7]. The capsule was noticeably thinner between 4 and 11 o'clock with a minimum thickness of 4.1 mm [95 % CI 3.3, 4.9] at 10 o'clock at the labral edge. Direct comparison between 0 and 5 mm between 9 and 3 o'clock showed that the hip capsule was significantly thicker at 5 mm from the labrum at 9 o'clock (p = 0.027), 10 o'clock (p = 0.032), 1 o'clock (p = 0.003), 2 o'clock (p = 0.001) and 3 o'clock (p = 0.001). CONCLUSIONS: The hip capsule was thickest between the 1 and 2 o'clock positions for all measured distances from the acetabular labrum and reached its maximum thickness at 2 o'clock, which corresponds to the location of the iliofemoral ligament.

A qualitative and quantitative analysis of the attachment sites of the proximal hamstrings.

PURPOSE: Proximal hamstring tears represent a challenge. Surgical repair of such tears has been reported utilizing both open and endoscopic techniques. It was hypothesized that the proximal attachments of the hamstring muscle group could be reproducibly and consistently measured from pertinent bony anatomical reference landmarks. METHODS: Fourteen fresh-frozen, human cadaveric specimens were dissected, and measurements were taken regarding the proximal attachments of the hamstring muscle group in reference to bony landmarks. A highly precise coordinate measuring device was used for three-dimensional measurements of tendon footprints and bony landmarks, and relevant distances between structures were calculated. RESULTS: The semitendinosus and long head of the biceps femoris shared a proximal origin (conjoined tendon), having an oval footprint with an average area of 567.0 mm(2) [95 % CI 481.0-652.9]. The semimembranosus (SM) footprint was crescent-shaped and located anterolateral to the conjoined tendon, with an average area of 412.4 mm(2) [95 % CI 371.0-453.8]. The SM footprint had an accessory tendinous extension that extended anteromedially forming a distinct footprint. A consistent bony landmark was found at the medial ischial margin, 14.6 mm [95 % CI 12.7-16.5] from the centre of the conjoined tendon footprint, which coincided with the distal insertion of the sacrotuberous ligament. CONCLUSION: The conjoined tendon was the largest attachment of the proximal hamstring group. Two other distinct attachment footprints were identified as the SM footprint and the accessory tendinous extension. The sacrotuberous ligament insertion served as a bony landmark. The anatomical data established in this study may aid in better restoring the anatomy during repair of proximal hamstring tears.

The ability of massive osteochondral allografts from the medial tibial plateau to reproduce normal joint contact pressures after glenoid resurfacing: the effect of computed tomography matching.

BACKGROUND: Current techniques for resurfacing of the glenoid in the treatment of arthritis are unpredictable. Computed tomography (CT) studies have demonstrated that the medial tibial plateau has close similarity to the glenoid. The purpose of this study was to assess contact pressures of transplanted massive tibial osteochondral allografts to resurface the glenoid without and with CT matching. METHODS: Ten unmatched cadaveric tibiae were used to resurface 10 cadaveric glenoids with osteochondral allografts. Five cadaveric tibiae and glenoids were CT matched and studied. An internal control group of 4 matched pairs of glenoids, with the contralateral glenoid transplanted to the opposite glenoid, was also included as a best-case scenario to measure the effects of the surgical technique. All glenoids were tested before and after grafting at different abduction and rotation angles, with recording of peak contact pressures. RESULTS: Peak contact pressures were not different from the intact state in the autografted group but were increased in both allografted groups. CT-matched tibial grafts had lower peak pressures than unmatched grafts. Peak pressures were on average 24.8% (range [18.3%, 29.6%]) greater than in the native glenoids for unmatched allografts, 21.8% ([17.0%, 25.5%]) greater for the matched allografts, and 4.9% ([3.8%, 5.5%]) greater for matched autografts. CONCLUSION: Osteochondral grafting from the medial tibial plateau to the glenoid is feasible but results in increased peak contact pressures. The technique is reproducible as defined by the autografted group. Contact pressures between native and allografted glenoids were significantly different. The clinical significance remains unknown. Peak pressures experienced by the glenoid seem highly sensitive to deviations from the native glenoid shape.

Biomechanical evaluation of knotless anterior and posterior Bankart repairs.

PURPOSE: The value of modern tape-like suture materials and the influence of the number of anchors inserted for arthroscopic Bankart repairs compared to the intact state have yet to be investigated. It was hypothesised: (1) suture-tape repairs will show higher biomechanical strength than common suture repairs, (2) four anchors will be stronger than three, and (3) the strength of the native capsulolabral complex will be greater than repairs. METHODS: Six matched-paired cadaveric shoulders received Bankart lesions/reconstructions and three underwent intact state testing. Anteroinferior repairs compared suture and suture-tape repairs using three anchors, while posteroinferior repairs compared three and four suture anchors using common sutures. An established testing protocol was run for biomechanical testing. RESULTS: There was no significant difference in the maximum loads, loads at 2 mm displacement, stiffness or energy between repair groups or between repairs and the intact state (n.s.). However, failure modes were different: 16/24 (66.7%) of the repair groups showed glenoid labrum detachment compared to 2/12 (16.7%) within the intact state group (P = 0.012). CONCLUSIONS: While biomechanical parameters of repairs and intact states showed equivalence, failure-mode analysis reaffirms previous findings that capsulolabrum complex refixation is weaker than the native attachment. Therefore, in daily clinical practice, type of suture is secondary and insertion of a fourth anchor will be unlikely to add strength but may confer additional risk and cost.

3D Analysis of Joint-Sparing Charcot-Marie-Tooth Surgery Effect on Initial Standing Foot Alignment.

BACKGROUND: The complex deformities in cavovarus feet of Charcot-Marie-Tooth (CMT) disease are difficult to evaluate. The aim of this study was to quantify the initial standing alignment correction achieved after joint-sparing CMT cavovarus reconstruction using pre- and postoperative weightbearing computed tomography (WBCT). METHODS: Twenty-nine CMT cavovarus reconstructions were retrospectively analyzed. Three-dimensional measurements were performed using semiautomated software (Bonelogic 2.1) to investigate changes in sagittal, axial, and coronal parameters. Pre- and postoperative data were compared, along with normative data. Correlation among the preoperative measurements and the amount of correction in sagittal, axial, and coronal parameters were analyzed. RESULTS: The sagittal, axial, and coronal malalignment of the hindfoot, and the sagittal and axial malalignment of the forefoot, was significantly improved after corrective surgery (P < .05). Sagittal Meary angle (from 14.8 to 0.1 degrees), axial talonavicular angle (TNA, from 3.6 to 19.2 degrees), and coronal hindfoot alignment (from 11.0 to -11.1 degrees) showed significant changes postoperatively (P < .001). Hindfoot, forefoot sagittal, and forefoot axial parameters reached comparable outcomes compared with normative value (P > .05). Regarding amount of correction, Spearman correlation demonstrated that axial Meary angle and TNA were most strongly related to improvement in sagittal Meary angle and coronal hindfoot alignment. CONCLUSION: Preoperative and postoperative WBCT measurements demonstrated that joint sparing CMT cavovarus reconstruction significantly improved sagittal, axial, and coronal deformities of CMT, and sagittal Meary angle was restored toward normative values. Apparent axial plane correction, the majority of which occurred at the talonavicular joint, had the strongest correlation with deformity correction in multiple planes. This suggests that soft tissue releases and correction of the talonavicular joint may be a key component of a cavovarus foot correction.

Charcot-Marie-Tooth Disease: A Surgical Algorithm.

In Charcot-Marie-Tooth (CMT) cavovarus surgery, a regimented approach is critical to create a plantigrade foot, restore hindfoot stability, and generate active ankle dorsiflexion. The preoperative motor examination is fundamental to the algorithm, as it is not only guides the initial surgical planning but is key in the decision making that occurs throughout the operation. Surgeons need to be comfortable with multiple techniques to achieve each surgical goal. There is no one operation that works for all patients with CMT. A plantigrade foot is the most important of the surgical goals as hindfoot stability and ankle dorsiflexion can be augmented with bracing.

Does Screw Order Matter? A Technique Tip to Prevent Loss of Fracture Reduction during Surgical Fixation of Lateral Malleolus Fractures.

When obtaining surgical fixation of lateral malleolus fractures, a cortical lag screw is commonly used to obtain anatomic reduction. Subsequently, a neutralization plate is applied. Slight loss of fracture reduction after plate placement occasionally occurs. Although this is frequently attributed to poor bone quality or suboptimal initial lag screw fixation, a frequently overlooked factor is screw order when applying the neutralization plate. The purpose of this technique tip is to highlight the biomechanical rationale behind this loss of reduction and advocate a specific screw order for lateral malleolus fixation.

Isolated Gastrocnemius Recession for Progressive Collapsing Foot Deformity.

INTRODUCTION: Progressive collapsing foot deformity (PCFD) is frequently associated with a gastrocnemius contracture. Surgical treatment of PCFD often includes a gastrocnemius recession in addition to other corrective procedures, which typically requires a period of restricted weight bearing postoperatively. Isolated gastrocnemius recession may allow passive correction of the deformity, improve orthotic fit, and obviate the need for full reconstruction and restricted weight bearing. The goal of this study was to evaluate patient-reported outcomes after an isolated gastrocnemius recession for flexible PCFD in patients anticipated to have difficulty with postoperative restricted weight bearing. METHODS: A total of 47 patients met the inclusion criteria: isolated gastrocnemius recession for flexible PCFD, no previous ipsilateral surgery, and more than 6 months of follow-up. Of 47 eligible patients, 29 (31 feet) participated. Available preoperative and postoperative patient-reported outcomes were gathered, including the Foot and Ankle Ability Measure Activities of Daily Living, visual analog scale, and the Patient-Reported Outcome Measurement Information System Physical Function Short Form 10a. In addition, patients were asked about satisfaction, willingness to undergo the procedure again, and whether orthotics provided better relief. RESULTS: At a mean of 5.1 (range, 0.6 to 9.0) years postoperatively, median Foot and Ankle Ability Measure Activities of Daily Living was 82.1, mean Patient-Reported Outcome Measurement Information System Physical Function Short Form 10a was 44.2, and median visual analog scale was 10 (of 100). Sixty-nine percent of patients were either satisfied or very satisfied, 69% would undergo the procedure again, and 62% reported improved relief with use of orthotics postoperatively. Among the 47 eligible patients, there were 5 (11%) subsequent flatfoot reconstructions. CONCLUSIONS: Isolated gastrocnemius recession for the management of flexible PCFD can be effective as this procedure demonstrated good outcomes scores with high procedural satisfaction and 11% of patients proceeding to subsequent flatfoot reconstruction. This alternative approach may be of particular value for patients anticipated to have difficulty with postoperative weight-bearing restrictions. LEVEL OF EVIDENCE: :IV.

Reliability of Fifth Metatarsal Base Fracture Classifications and Current Management.

BACKGROUND: Classification of fifth metatarsal base fractures has been a source of confusion since originally described by Jones in 1902. Zone classifications have been described but never evaluated for reliability. The most recent classification, metaphyseal vs meta-diaphyseal, may be unknown to many surgeons. The purpose of this study was to evaluate reliability of American Orthopaedic Foot & Ankle Society (AOFAS) members classifying fifth metatarsal base fractures and current management of these fractures. METHODS: A survey was emailed to AOFAS members including radiographs of 18 fifth metatarsal base fractures. Demographic information was collected in addition to evaluation of the radiographs. Interrater reliability was assessed for each measurement: presence of Jones fracture, zone classification, and metaphyseal vs metaphyseal-diaphyseal, using Fleiss kappa. After 3 weeks, a second email was sent to the members asking to retake the survey to evaluate intrarater reliability. Respondents were asked which region is a Jones fracture, which classification is used, if symptomatic zone 2 and 3 fractures are treated similarly, and what fractures are operative in healthy symptomatic acute fractures. RESULTS: A total of 223 AOFAS members, with a median time in practice of 12 years (range 0-50), completed the initial survey. Eighty members (36%) repeated the survey for intrarater comparison. Interrater reliability was moderate for Jones and zone classification but substantial for the 2-zone metaphyseal/meta-diaphyseal classification. The median intrarater kappa was 0.78, 0.75, and 0.78 for Jones, zone, and metaphyseal/meta-diaphyseal respectively. Seventy percent of respondents treat zones 2 and 3 similarly, and approximately 60% consider an acute symptomatic fracture identified as Jones, zone 2 or zone 3 operative. CONCLUSION: A 2-zone system may be the best available classification for fifth metatarsal base fractures given high interrater reliability and 70% of AOFAS members treat zones 2 and 3 in similar fashion. LEVEL OF EVIDENCE: Level III, diagnostic study.

Abnormal Bone Morphology in Charcot-Marie-Tooth Disease.

BACKGROUND: Although long suspected, it has yet to be shown whether the foot and ankle deformities of Charcot-Marie-Tooth disease (CMT) are generally associated with abnormalities in osseous shape. Computed tomography (CT) was used to quantify morphologic differences of the calcaneus, talus, and navicular in CMT compared with healthy controls. METHODS: Weightbearing CT scans of 21 patients (27 feet) with CMT were compared to those of 20 healthy controls. Calcaneal measurements included radius of curvature, sagittal posterior tuberosity-posterior facet angle, and tuberosity coronal rotation. Talar measurements included axial and sagittal body-neck declination angle, and coronal talar head rotation. Surface-mesh model analysis of the hindfoot was performed comparing the average of the CMT cohort to the controls using a CT analysis software (Disior Bonelogic 2.0). Means were compared with a t test (P < .05). RESULTS: CMT patients had significantly less talar sagittal declination vs controls (17.8 vs 25.1 degrees; P < .05). Similarly, CMT patients had less talar head coronal rotation vs controls (30.8 vs 42.5 degrees; P < .001). The calcaneal radius of curvature in CMT patients was significantly smaller than controls (822.8 vs 2143.5 mm; P < .05). CMT sagittal posterior tuberosity-posterior facet angle was also significantly different from that of controls (60.3 vs 67.9 degrees respectively; P < .001).Surface-mesh model analysis demonstrated the largest differences in morphology at the navicular tuberosity, medial talar head, sustentaculum tali, and anterior process of the calcaneus. CONCLUSION: This is the first study to quantify the morphologic differences in hindfoot osteology seen in CMT patients. Patients identified with osseous changes of the calcaneus, especially a smaller axial radius of curvature, may benefit from a 3-dimensional osteotomy for correction.

Endoscopic Haglund's Resection and Percutaneous Double-Row Insertional Achilles Repair.

Insertional Achilles tendinopathy can be a debilitating condition that often fails to improve with nonsurgical management such as bracing and physical therapy. Traditional surgical techniques include an open debridement of the diseased tendon and resection of calcaneal spurs. This is followed by repair of the tendon. Suture anchors are often used to secure the tendon, but recent advances in tendon fixation, including the advent of double-row repairs, has allowed better biomechanical repairs and faster rehabilitation. Additionally, minimally invasive surgery and endoscopic techniques have advanced to allow successful treatment of all aspects of the condition while minimizing wound complications and infection. The authors present a technique to treat insertional Achilles tendinopathy and calcaneal bone spurs using minimally invasive surgery techniques while also incorporating a percutaneous double-row suture anchor repair. The technique utilizes 4 portals to access 2 endoscopic working planes. The burr is inserted deep to the tendon and the calcaneoplasty is performed. Subsequently, the endoscope is inserted alongside a shaver to remove bony debris and debulk the anterior aspect of the Achilles areas of tendinopathy. Following this, the portals are used to place a double-row suture anchor repair.Levels of Evidence: Level V.

Addressing Common Questions About Traveling by Air After Orthopedic Surgery.

Many patients have questions about traveling by air after orthopedic surgery. The goal of this review was to provide a guide to addressing these issues to better prepare patients for air travel. A comprehensive literature review was conducted to address patient questions regarding metal detectors, as well as deep venous thrombosis risk with flying. Further, patient questions pertaining to specific airlines, airports, and Transportation Security Administration policies were answered through direct discussion with representatives, website review, and internet research. Ultimately, providers should be aware of the many challenges that orthopedic patients face during air travel, and patients should consult their providers before making travel plans. Airline passengers are likewise encouraged to equip themselves with the information presented in this article, to best advocate for themselves. This guide should be used as a reference tool, providing up-to-date information about air travel after orthopedic surgery to both patients and providers alike. [Orthopedics. 2021;44(6):e719-e723.].

Biomechanical Comparison of Achilles Tendon Pullout Strength Following Midline Tendon-Splitting and Endoscopic Approaches for Calcaneoplasty.

BACKGROUND: Calcaneoplasty is a common procedure performed for the management of Haglund's syndrome when nonoperative management fails. Midline tendon-splitting and endoscopy are 2 common approaches to calcaneoplasty. Studies have suggested that an endoscopic approach may allow earlier return to activity and superior outcomes, but there are no biomechanical or clinical studies to validate these claims. The goal of this study was to quantify and compare Achilles tendon pullout strength following midline tendon-splitting and endoscopic calcaneoplasty in cadaveric specimens. METHODS: Twelve match-paired cadaveric specimens were randomly divided into 2 groups: endoscopic and midline tendon-split. Following calcaneoplasty, fluoroscopy was used to match bone resection and the Achilles was loaded to failure in a mechanical testing system. A paired-samples t test was conducted to compare bone resection height, bone resection angle, load to failure, and mode of failure. RESULTS: The endoscopic approach yielded a 204% greater postsurgical pullout strength for the Achilles tendon than the midline tendon-split (1368 ± 370 N vs 450 ± 192 N, respectively) (P < .05). There were no differences in resection angle or resection height. All specimens failed due to bone or tendon avulsion. CONCLUSION: Endoscopic calcaneoplasty had more than 3 times greater pullout strength than the midline tendon-splitting approach. CLINICAL RELEVANCE: This may allow earlier return to functional rehabilitation following endoscopic calcaneoplasty, but further studies are needed to determine if these differences are clinically significant. Further understanding of the time-zero biomechanics following calcaneoplasty may provide guidance regarding postoperative management with respect to surgical approach.

Use of 3D Prints to Compare the Efficacy of Three Different Calcaneal Osteotomies for the Correction of Heel Varus.

BACKGROUND: Cavovarus deformity of the hindfoot is typically caused by neurologic disorders. Multiple osteotomies have been described for the correction of varus deformity but without clinical comparison. In this study, we used 18 identical 3-dimensional (3D) prints of a patient with heel varus to compare the operative correction obtained with Dwyer, oblique, and Z osteotomies. METHODS: A computed tomography (CT) scan of a patient with heel varus was used to create 18 identical 3D prints of the talus, calcaneus, and cuboid. Coordinate frames were added to the talus and calcaneus to evaluate rotation. The prints were then divided into 3 groups of 6 models each. A custom jig precisely and accurately replicated each osteotomy. Following the simulated operations, cut models were CT scanned and compared with 6 uncut models. Measurements were calculated using multiplanar reconstruction image processing. An analysis of variance (ANOVA) was performed on the initial data to determine significant differences among the measured variables. A Tukey Studentized range test was run to compare variables that showed statistically significant differences using the ANOVA. RESULTS: The coronal angle of the Dwyer and oblique osteotomies was significantly less than that of the Z osteotomy ( P < .05). The axial angle, lateral displacement, and calcaneal shortening of the uncut model and Z osteotomy were significantly less than the Dwyer and oblique osteotomies. CONCLUSIONS: Dwyer, oblique, and Z osteotomies did not create either lateral translation or coronal rotation without the addition of a lateralizing slide or rotation of the posterior tuberosity. CLINICAL RELEVANCE: Dwyer and oblique osteotomies would be best suited for mild deformity, yet the amount of calcaneal shortening must be acknowledged. A Z osteotomy is a complex procedure that has the capability of correcting moderate-severe coronal plane rotation but fails to provide lateralization of the pull of the Achilles insertion.

An anatomical study of the acetabulum with clinical applications to hip arthroscopy.

BACKGROUND: The clock face has been employed to define the position of labral pathology in relation to identifiable arthroscopically relevant acetabular landmarks. The purpose of this study was to qualitatively and quantitatively describe arthroscopically relevant anatomy of the acetabulum. We aimed to present a surgical landmark that is located in close proximity to the usual location of labral pathology as an alternative to the midpoint of the transverse acetabular ligament as a reference point. METHODS: Fourteen fresh-frozen cadaveric hemipelves were dissected to evaluate osseous landmarks and relevant surrounding soft-tissue structures of the acetabulum. With use of a coordinate-measuring device, we determined the location, orientation, and relationship of key arthroscopic landmarks and the footprint areas formed by the insertions of the rectus femoris, capsule, and labrum. RESULTS: An analysis of variability of reference points around the acetabulum in relation to the anterior inferior iliac spine (AIIS) revealed that the superior margin of the anterior labral sulcus (psoas-u) was the most consistent anatomic landmark. The AIIS comprised superior and inferior facets, demarcated by the origins of the direct head of the rectus femoris and the iliocapsularis. The inferolateral corner of the footprint of the direct head of the rectus femoris was located 19.2 mm (95% confidence interval [CI], 18.0 to 20.4 mm) from the acetabular rim and the inferolateral aspect of the iliocapsularis footprint, 12.5 mm (95% CI, 10.1 to 15.0 mm) from the rim. CONCLUSIONS: The superior margin of the anterior labral sulcus (psoas-u) was a reliable landmark for reference of the clock face on the acetabulum. We propose that this point, denoting 3:00, be adopted as the new standard clock-face reference for intra-articular hip structures because of its universal presence and reliable arthroscopic visualization. This marker is also beneficial because of its proximity to the typical location of labral pathology. The data presented provide a comprehensive analysis of pertinent arthroscopically relevant acetabular anatomy. CLINICAL RELEVANCE: The establishment of a new standard reference point within the acetabulum will enhance the consistency of interpretation of the location of labral pathology and improve arthroscopic orientation and navigation.

Surgically Relevant Bony and Soft Tissue Anatomy of the Proximal Femur.

BACKGROUND: Hip endoscopy facilitates the treatment of extra-articular disorders of the proximal femur. Unfortunately, current knowledge of proximal femur anatomy is limited to qualitative descriptions and lacks surgically relevant landmarks. PURPOSE: To provide a quantitative and qualitative analysis of proximal femur anatomy in reference to surgically relevant bony landmarks. STUDY DESIGN: Descriptive laboratory study. METHODS: Fourteen cadaveric hemipelvises were dissected. A coordinate measuring device measured dimensions and interrelationships of the gluteal muscles, hip external rotators, pectineus, iliopsoas, and joint capsule in reference to osseous landmarks. RESULTS: The vastus tubercle, superomedial border of the greater trochanter, and femoral head-neck junction were distinct and reliable osseous landmarks. The anteroinferior tip of the vastus tubercle was 17.1 mm (95% CI: 14.5, 19.8 mm) anteroinferior to the center of the gluteus medius lateral insertional footprint and was 22.9 mm (95% CI: 20.1, 25.7 mm) inferolateral to the center of the gluteus minimus insertional footprint. The insertions of the piriformis, conjoint tendon of the hip (superior gemellus, obturator internus, and inferior gemellus), and obturator externus were identified relative to the superomedial border of the greater trochanter. The relationship of the aforementioned footprints were 49% (95% CI: 43%, 54%), 42% (95% CI: 33%, 50%), and 64% (95% CI: 59%, 69%) from the anterior (0%) to posterior (100%) margins of the superomedial border of the greater trochanter, respectively. The hip joint capsule attached distally on the proximal femur 18.2 mm (95% CI: 14.2, 22.2 mm) from the head-neck junction medially on average. CONCLUSION: The vastus tubercle, superomedial border of the greater trochanter, and the femoral head-neck junction were reliable osseous landmarks for the identification of the tendinous and hip capsular insertions on the proximal femur. Knowledge of the interrelationships between these structures is essential for endoscopic navigation and anatomic surgical repair and reconstruction. CLINICAL RELEVANCE: The qualitative and quantitative clinically relevant anatomic data presented here will aid in the diagnosis of proximal femur pathology and will provide a template for anatomic repair or reconstruction.