Osteochondral lesions of the humeral trochlea in the young athlete

Objective  The purpose of this study was to characterize the variety of osteochondral abnormalities of the humeral trochlea in the pediatric athlete. Materials and methods  Patients with trochlear abnormalities were identified through keyword search of radiology dictations from 1999 to 2007. The patient’s medical record, imaging studies, and surgical reports were reviewed. The osteochondral lesions were categorized based on the imaging appearance. Surgical results were reviewed in conjunction with the imaging findings. Results  Eighteen patients were identified. Trochlear lesions were stratified into two imaging groups: Osteochondral injury/osteochondritis dissecans (OCD) vs. avascular necrosis (AVN). The osteochondral injury group was stratified into medial and lateral trochlear abnormalities. The medial lesions (n = 3) were small (<6 mm) and were located on the posterior articular surface of the medial trochlea. The lateral lesions (n = 10) were larger (10–14 mm), circumscribed, and were located on the posterior inferior aspect of the lateral trochlea. Trochlear AVN (n = 5) affected development of the lateral trochlea (type A) or both the medial and lateral aspects of the trochlea (type B). AVN occurred exclusively in athletes with history of remote distal humeral fracture. Seven of the 18 patients underwent elbow arthroscopy. Surgical findings and treatment regimens are summarized. Conclusion  Trochlear lesions should be considered in throwing athletes presenting with medial elbow pain and flexion contracture/extension block. Medial trochlear osteochondral injuries may result from posteromedial olecranon abutment. Lateral OCD lesions occur in a characteristic vascular watershed zone resulting from the unique blood supply of the trochlea. Trochlear AVN may be unmasked years following treated distal humeral fracture when the athletic demands upon the adolescent elbow increase, revealing the altered growth and biomechanics.     

Chondral thickness and radii of curvature of the femoral condyles and talar trochlea

To localize optimal donor regions for osteochondral graft transplantation, the chondral thickness and the radii of curvature of femoral condyles and the talar trochlea were determined. Optosil impressions of the articular surfaces of ten formalin fixed distal femora and talar domes were prepared. Therefrom, 5-mm thick frontal sections were made in order to measure the radii of curvature. Femoral condyles and talar trochleas were sliced sagittally into 2-mm thick sections. Chondral thickness was measured on x-rays. Talar cartilage thickness measured 0.7 to 2.0 mm. Cartilage thickness of the femoral condyles was 0.7 mm to 3.1 mm. The smallest radial values of the talar surface were proximal and distal. Flattening of the medial and lateral talar margins and of the central articular surface was evident. For the femur, the curvature was greater in the edge areas than in the central region. For talar defects, the grafts should be taken from the condylar edges, where the chondral thickness is decreased.     

An anterior ankle arthroscopic technique for retrograde osteochondral autograft transplantation of posteromedial and central talar dome cartilage defects

Purpose

The purpose of this study was to present an arthroscopic technique for the treatment for posteromedial and central cartilage defects of the talus using anterior arthroscopic portals and without performing a medial malleolar osteotomy.

Methods

Nine fresh cadavers were dissected. Autografts were implanted under arthroscopy using a retrograde osteochondral transplantation system, and their position was estimated using specific angular calibrators and later confirmed by software analysis of two photographs of the disarticulated ankle joint.

Results

In eight cases, the congruence between the surrounding articular cartilage and the cartilage of the graft was high, with differences measuring <1 mm. There were no iatrogenic cartilage lesions of the tibial plafond and no fractures of the talus. All the autografts remained stable during full range of motion cycles of the ankle joint. One failure was reported.

Conclusion

This cadaveric study showed that the retrograde osteochondral autograft transplantation technique in the talus is feasible. It can be used to restore the posteromedial and central talar articular surfaces using conventional ankle arthroscopic instrumentation and anterior arthroscopic portals without resorting to a medial malleolar osteotomy. Further clinical and biomechanical studies are required to prove the efficacy of this technique and its reproducibility in routine clinical practice.     

Oblique osteochondral plugs transplantation technique for osteochondritis dissecans of the elbow joint

Autologous osteochondral transplantation is an established surgical procedure for osteochondritis dissecans (OCD) of the knee, and has recently been applied in cases of advanced-staged OCD of the elbow. The elbow procedure; however, is more technically demanding than for the knee. One reason is the difficulties of perpendicular insertion of large-diameter osteochondral plugs to the humeral capitellum with a small, narrow operative field in the humeroradial joint. Furthermore, if the OCD lesion is located on the lateral site of the capitellum, the creation of recipient holes perpendicular to the joint surface is difficult due to the risk of damaging the lateral wall of the capitellum. To avoid such difficulties, we developed a new technique by which 6.5 and/or 8.5 mm diameter plugs are harvested from the ipsilateral knee, having an oblique cartilage surface relative to the long axis of the plugs. These are then inserted into the recipient holes which are created obliquely from the lateral and distal to medial and proximal directions in the capitellum at an angle complimentary to the harvested plugs. This technique allows easy insertion of large-diameter plugs into recipient holes in a restricted operative field, even if the OCD lesion is located in the lateral site.     

Biomechanical and topographic considerations for autologous osteochondral grafting in the knee

This study characterizes the donor and recipient sites involved in osteochondral autograft surgery of the knee with respect to articular cartilage contact pressure, articular surface curvature, and cartilage thickness. Five cadaveric knees were tested in an open chain activity simulation and kinematic data were obtained at incremental knee flexion angles from 0 degrees to 110 degrees. Surface curvature, cartilage thickness, and contact pressure were determined using a stereophotogrammetry method. In all knees, the medial trochlea, intercondylar notch, and lateral trochlea demonstrated nonloadbearing regions. Donor sites from the distal-medial trochlea were totally nonloadbeadng. For the intercondylar notch, lateral trochlea, and proximal-medial trochlea, however, the nonloadbearing areas were small, and typical donor sites in these areas partially encroached into adjacent loadbearing areas. The lateral trochlea (77.1 m(-1)) was more highly curved than the typical recipient sites of the central trochlea (23.3 m(-1)), medial femoral condyle (46.8 m(-1)), and lateral femoral condyles (42.9 m(-1)) (P < 0.05). Overall, the donor sites had similar cartilage thickness (average, 2.1 mm) when compared with the typical recipient sites (average, 2.5 mm). The lateral trochlea and medial trochlea curvatures were found to better match the recipient sites on the femoral condyles, while the intercondylar notch better matched the recipient sites of the central trochlea. The distal-medial trochlea was found to have the advantage of being nonloadbearing. Preoperative planning using the data presented will assist in more conforming, congruent grafts, thereby maximizing biomechanical function.     

Medial approaches to osteochondral lesion of the talus without medial malleolar osteotomy

The purpose of this study was to determine the area of the talus that can be reached through combined anterior and posterior arthrotomy without medial malleolar osteotomy. Five fresh-frozen cadaver foot-ankle specimens were examined using posteromedial approach and anteromedial approach. We calculated the size of the marked area beginning from the posteromedial corner of the talus in the posteromedial approach and beginning from the anteromedial corner in the anteromedial approach. From the posteromedial talus, we can access 33% of the talus’ AP length and 30% of its medial to lateral length through a posteromedial approach. From the anteromedial arthrotomy, 50% of the AP length and 31% of the medial to lateral length can be reached. This leaves approximately 20% that is not accessible. If the osteochondral lesion is within the accessible area through either a posteromedial or anteromedial approach as viewed on MRI/CT, it can be safely reached without a medial malleolar osteotomy.     

Treatment of osteochondral lesions of the talus: a systematic review

The aim of this study was to summarize all eligible studies to compare the effectiveness of treatment strategies for osteochondral defects (OCD) of the talus. Electronic databases from January 1966 to December 2006 were systematically screened. The proportion of the patient population treated successfully was noted, and percentages were calculated. For each treatment strategy, study size weighted success rates were calculated. Fifty-two studies described the results of 65 treatment groups of treatment strategies for OCD of the talus. One randomized clinical trial was identified. Seven studies described the results of non-operative treatment, 4 of excision, 13 of excision and curettage, 18 of excision, curettage and bone marrow stimulation (BMS), 4 of an autogenous bone graft, 2 of transmalleolar drilling (TMD), 9 of osteochondral transplantation (OATS), 4 of autologous chondrocyte implantation (ACI), 3 of retrograde drilling and 1 of fixation. OATS, BMS and ACI scored success rates of 87, 85 and 76%, respectively. Retrograde drilling and fixation scored 88 and 89%, respectively. Together with the newer techniques OATS and ACI, BMS was identified as an effective treatment strategy for OCD of the talus. Because of the relatively high cost of ACI and the knee morbidity seen in OATS, we conclude that BMS is the treatment of choice for primary osteochondral talar lesions. However, due to great diversity in the articles and variability in treatment results, no definitive conclusions can be drawn. Further sufficiently powered, randomized clinical trials with uniform methodology and validated outcome measures should be initiated to compare the outcome of surgical strategies for OCD of the talus.     

The effect of overlapping on the primary stability of osteochondral grafts in mosaicplasty

Our goal was to determine the primary stability of overlapping osteochondral grafts used in mosaicplasty by studying the effect of overlapping in an ex vivo model. Osteochondral grafts, 10 mm in diameter, were transplanted from the trochlea of cow femurs to the weight-bearing area of the lateral femoral condyle with 0, 15, or 30% overlap. The grafts were pushed in with a probe at a rate of 2 mm/min, and load (N)-displacement (mm) curves were recorded. In Group I (control, 0% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 572.3 +/- 273.6 and 999.3 +/- 427.6 N, respectively. In Group II (15% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 263.6 +/- 91.7 and 746.6 +/- 88.0 N, respectively. In Group III (30% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 179.4 +/- 31.2 and 657.0 +/- 106.5 N, respectively. The loads that were necessary to produce a 1-mm dent in the grafts were significantly different between Groups I and II and Groups I and III (p < 0.05). These results suggest that stability may be reduced by graft overlapping in mosaicplasty surgery. The results of this ex vivo animal study contribute to a more complete understanding of the primary stability of osteochondral grafts in an overlapping position as well as postoperative protocols.     

Contact pressure at osteochondral donor sites in the patellofemoral joint

BACKGROUND: The lowest contact pressure point is presumed to be the best site to harvest an osteochondral plug and minimize morbidity. HYPOTHESIS: Patellofemoral contact pressures are not uniform and are lowest along the medial patellofemoral articulation. STUDY DESIGN: Controlled laboratory study. METHODS: Seven cadaveric knees were tested with an electroresistive, dynamic pressure sensor placed onto the femoral side of the patellofemoral joint. The extensor mechanism was loaded with 89.1 N and 178.2 N, and the knee was manually cycled 3 times (0 degrees -105 degrees ) per load. Mean trochlear pressures were calculated. RESULTS: Mean contact pressures were greatest in the central trochlea (5.80 kgf/cm(2)), followed by the lateral (2.56 kgf/cm(2)) and medial trochlea (1.60 kgf/cm(2)) at 89.1 N (P <.05). At 178.2 N, pressures increased to 9.47, 5.81, and 2.75 kgf/cm(2), respectively (P <.05). Lateral trochlear pressures decreased moving distally from 1.25 to 0.50 kgf/cm(2) at 89.1 N and 4.57 to 1.29 kgf/cm(2) at 178.2 N. CONCLUSIONS: Contact pressures are lowest along the medial trochlea and decrease distally along the lateral trochlea. CLINICAL RELEVANCE: Osteochondral plugs from the medial femoral trochlea may be desirable if trochlear size permits. If harvesting from the lateral femoral trochlea, consider harvesting distally near the sulcus terminalis.     

CT changes after trochleoplasty for symptomatic trochlear dysplasia

Trochlear dysplasia is an important risk factor for patellar instability. Because of a decreased trochlear depth in combination with a low lateral femoral condyle, the patella cannot engage properly in the trochlea. Trochleoplasty is a surgical procedure, which strives to correct such bony abnormalities. The aim of this study was to describe morphological features of trochlear dysplasia and the corrective changes after trochleoplasty on CT scan. The study group consists of 17 knees with trochlear dysplasia having undergone trochleoplasty for recurrent patellofemoral dislocation at a mean age of 22.4 years. The evaluation consisted in pre- and postoperative measurements on the proximal and distal trochlea on transverse CT scans in order to determine the morphological features. We measured the transverse position and depth of the trochlear groove, the transverse position of the patella, the ratio between the posterior patellar edge and the trochlear groove, the lateral patellar inclination angle, the sulcus angle, and the lateral trochlear slope. The trochlear groove lateralised a mean of 6.1 mm in the proximal aspect and 2.5 mm in the distal aspect of the trochlea, while the patella medialised a mean of 5 mm. Preoperatively the patella was lateral in relation to the trochlear groove in 13 cases, neutral in two cases, and medial in two cases. Postoperatively it was lateral in four cases, in neutral position in seven cases, and medialised in six cases, referenced to the trochlear groove. The trochlear depth increased from 0 to 5.9 mm postoperatively in the proximal aspect of the trochlea, and from 5.5 to 8.3 mm postoperatively in the distal trochlea. The lateral patellar inclination angle decreased from a mean of 21.9° to a mean of 7.8°. The sulcus angle decreased from a mean of 172.1° to a mean of 133° in the proximal trochlea and from a mean of 141.9° to a mean of 121.7° in the distal trochlea. The lateral trochlear slope changed from 2.8° to 22.7° in the proximal and from 14.9° to 26.9° in the distal part of the trochlea. In the CT scan patients with trochlear dysplasia demonstrated a poor depth, or even a flat or convex trochlea with a greater sulcus and lateral trochlear slope angle, a lateralised patella to the trochlear groove with poor congruency, and a greater lateral patellar inclination angle. Trochleoplasty can correct the pathological features of trochlear dysplasia by surgically creating more normal anatomy. The goal of this surgical procedure is to steepen and lateralise the trochlear groove for a better engagement of the patella.     

A novel implantation technique for engineered osteo-chondral grafts

We present a novel method to support precise insertion of engineered osteochondral grafts by pulling from the bone layer, thereby minimizing iatrogenic damage associated with direct manipulation of the cartilage layer. Grafts were generated by culturing human expanded chondrocytes on Hyaff^®-11 meshes, sutured to Tutobone^® spongiosa cylinders. Through the bone layer, shaped to imitate the surface-contours of the talar dome, two sutures were applied: the first for anterograde implantation, to pull the graft into the defect, and the second for retrograde correction, in case of a too deep insertion. All grafts could be correctly positioned into osteochondral lesions created in cadaveric ankle joints with good fit to the surrounding cartilage. Implants withstood short-term dynamic stability tests applied to the ankle joint, without delamination or macroscopic damage. The developed technique, by allowing precise and stable positioning of osteochondral grafts without iatrogenic cartilage damage, is essential for the implantation of engineered tissues, where the cartilage layer is not fully mechanically developed, and could be considered also for conventional autologous osteochondral transplantation.     

Osteochondral lesions of the talus in a sports medicine clinic. A new radiographic technique and surgical approach

A retrospective review of 11 patients seen at the University of British Columbia Sports Medicine Clinic with osteochondral lesions of the talus was undertaken. From our data, a number of points became apparent. There was a predominance of posteromedial talar dome lesions. A flexion-inversion ankle injury could be documented in the majority of cases. There was frequently a long delay in diagnosing these ankle sprain mimics. Historical details which should raise one's index of suspicion include: (1) history of flexion-inversion injury; (2) exercise-related ankle pain; (3) sensations of "clicking and catching"; and (4) persistent swelling. Surgery produced consistently good early results in these active patients without osteotomizing the medial malleolus. Experimental analysis and clinical experience suggest that the optimal radiographic technique for identifying the posteromedial osteochondral lesion consists of an anteroposterior view of the ankle in maximum plantar flexion with the kilovoltage set at 70.     

Topographic matching of selected donor and recipient sites for osteochondral autografting of the articular surface of the femoral condyles

The purpose of this study was to define the topography of the articular surface of the femoral condyles and to develop a method for computerized topographic matching of donor and recipient sites for osteochondral transplantation. The condyles of seven fresh cadaveric femurs were mounted on the rotating stage of a laser-based coordinate measuring machine. An anatomic coordinate system defining the articular surface of the condyles was created. Customized software was developed to allow selection and topographic matching of osteochondral graft donor and recipient sites from any location on the surface of the condyles. For cartilage defects within the weightbearing portions of the medial or lateral femoral condyles, grafts taken from sites from the most medial or lateral portions of the patellar groove provided a significantly better topographic match than did grafts taken from the central intercondylar notch.     

Helical CT of talar fractures

 Since the degree of comminution, fracture alignment, and articular congruity of talar fractures are important determinants of treatment, we review the helical CT technique for detecting and assessing the extent of acute talar fractures. Helical CT can be used to classify talar neck fractures which often cannot be determined by radiography. It is also useful in detecting posterior process, lateral process, and avulsion fractures, as well as acute osteochondral fractures. Multiplanar CT using 1-mm acquisitions allows optimal evaluation, detects fractures initially missed on radiographs, and determines further extent of fractures.     

Osteochondral defects in the human knee: influence of defect size on cartilage rim stress and load redistribution to surrounding cartilage

PURPOSE: To determine the influence of osteochondral defect size on defect rim stress concentration, peak rim stress, and load redistribution to adjacent cartilage over the weightbearing area of the medial and lateral femoral condyles in the human knee. METHODS: Eight fresh-frozen cadaveric knees were mounted at 30 degrees of flexion in a materials testing machine. Digital electronic pressure sensors were placed in the medial and lateral compartments of the knee. Each intact knee was first loaded to 700 N and held for 5 seconds. Dynamic pressure readings were recorded throughout the loading and holding phases. Loading was repeated over circular osteochondral defects (5, 8, 10, 12, 14, 16, 18, and 20 mm) in the 30 degrees weightbearing area of the medial and lateral femoral condyles. RESULTS: Stress concentration around the rims of defects 8 mm and smaller was not demonstrated, and pressure distribution in this size range was dominated by the menisci. For defects 10 mm and greater, distribution of peak pressures followed the rim of the defect with a mean distance from the rim of 2.2 mm on the medial condyle and 3.2 mm on the lateral condyle. An analysis of variance with Bonferroni correction revealed a statistically significant trend of increasing radius of peak pressure as defect size increased for defects from 10 to 20 mm (P = .0011). Peak rim pressure values did not increase significantly as defects were enlarged from 10 to 20 mm. Load redistribution during the holding phase was also observed. CONCLUSIONS: Rim stress concentration was demonstrated for osteochondral defects 10 mm and greater in size. This altered load distribution has important implications relating to the long-term integrity of cartilage adjacent to osteochondral defects in the human knee. Although the decision to treat osteochondral lesions is certainly multifactorial, a size threshold of 10 mm, based on biomechanical data, may be a useful adjunct to guide clinical decision making.     

Sex determination from talus in Chinese population by three-dimensional measurement approach

ObjectiveThe determination of sex is an essential part of building the biological profile for unknown human remains. Sex determination from talus in Chinese population has been rarely reported. The aim of this study was to determine sex by discriminant function analysis through talus measurement in Chinese population.Methods48 male and 47 female Chinese northeast subjects were taken in this research. The ankle joints of these subjects were scanned by CT. In total, thirteen indexes were measured through Mimics and Magics software. Length and breadth indexes of total talus, trochlea, talar head, medial and lateral malleolus articular surface were mainly selected. Nine of them were measured through Mimics software. The other four indexes were measured through Magics software. All data were analyzed by independent-samples t-test in SPSS and Stata software. Discriminant function equations were generated for sex determination.ResultsAll the indexes were normally distributed. No significant difference between left and right talus in either males or females was identified (P > 0.05). All results showed significant sexual difference (P < 0.05) except posterior breadth of trochlea. The average accuracy of sex determination ranged from 95.85% to 98.45% in the direct method and 98.95% in the stepwise method.ConclusionsLength indexes showed higher accuracy rate than breadth ones. Length of lateral malleolus articular surface was the best discriminator of sexual dimorphism. Talus was proved effective for sex determination in Chinese population. This study provided a remarkable reference for sex determination in forensic science.     

基于CT三维重建分析距骨软骨下骨囊肿形态学及分布特点

目的:通过CT三维重建分析距骨软骨下骨囊肿的形态学及分布特点。方法:在天津医院影像报告数据库中检索2015—2020年经踝关节或足部CT扫描后诊断为距骨软骨下骨囊肿患者176例,其中男77例,女99例;年龄14~84岁［（56.1±14.0）岁］。通过Mimics 20.0软件三维重建距骨及囊肿区域后,构建田字解剖网格...     

Osteochondral transplantation using autografts from the upper tibio-fibular joint for the treatment of knee cartilage lesions

Purpose

Treatment of large cartilage lesions of the knee in weight-bearing areas is still a controversy and challenging topic. Autologous osteochondral mosaicplasty has proven to be a valid option for treatment but donor site morbidity with most frequently used autografts remains a source of concern. This study aims to assess clinical results and safety profile of autologous osteochondral graft from the upper tibio-fibular joint applied to reconstruct symptomatic osteochondral lesions of the knee.

Methods

Thirty-one patients (22 men and 9 women) with grade 4 cartilage lesions in the knee were operated by mosaicplasty technique using autologous osteochondral graft from the upper tibio-fibular joint, between 1998 and 2006. Clinical assessment included visual analog scale (VAS) for pain and Lysholm score. All patients were evaluated by MRI pre- and post-operatively regarding joint congruency as good, fair (inferior to 1 mm incongruence), and poor (incongruence higher than 1 mm registered in any frame). Donor zone status was evaluated according to specific protocol considering upper tibio-fibular joint instability, pain, neurological complications, lateral collateral ligament insufficiency, or ankle complaints.

Results

Mean age at surgery was 30.1 years (SD 12.2). In respect to lesion sites, 22 were located in weight-bearing area of medial femoral condyle, 7 in lateral femoral condyle, 1 in trochlea, and 1 in patella. Mean follow-up was 110.1 months (SD 23.2). Mean area of lesion was 3.3 cm² (SD 1.7), and a variable number of cylinders were used, mean 2.5 (SD 1.3). Mean VAS score improved from 47.1 (SD 10.1) to 20.0 (SD 11.5); p = 0.00. Similarly, mean Lysholm score increased from 45.7 (SD 4.5) to 85.3 (SD 7.0); p = 0.00. The level of patient satisfaction was evaluated, and 28 patients declared to be satisfied/very satisfied and would do surgery again, while 3 declared as unsatisfied with the procedure and would not submit to surgery again. These three patients had lower clinical scores and kept complaints related to the original problem but unrelated to donor zone. MRI score significantly improved at 18–24 months comparing with pre-operative (p = 0.004). No radiographic or clinical complications related to donor zone with implication in activity were registered.

Conclusions

This work corroborates that mosaicplasty technique using autologous osteochondral graft from the upper tibio-fibular joint is effective to treat osteochondral defects in the knee joint. No relevant complications related to donor zone were registered.

Level of evidence

Case series, Level IV.     

Recurrent patellar dislocation after medial patellofemoral ligament reconstruction

We report on three cases of recurrent lateral patellar dislocation following a medial patellofemoral ligament (MPFL) reconstruction for patellar instability. In all three cases, an isolated MPFL reconstruction was performed with a double autogenous gracilis graft. The patellar fixation was done through bone tunnels. All three patients presented with a definite moderate to severe traumatic episode resulting in a recurrent patella dislocation and a transverse avulsion fracture at the medial rim of the patella. All three were treated by an open reduction and internal fixation with good results. No complication or recurrent dislocations occurred. We suggest that this complication is caused by the original underlying pathology such as dysplastic trochlea, abnormal TT–TG, patella alta and hyperlaxity, resulting a greater reliance upon the reconstructed MPFL for patellar stability. When subjected to a severe stress, the graft, which is stronger and stiffer than the original MPFL, will cause a fracture through the medial edge of the patella. This weak area results from the previous drill holes, which act as stress risers.