[Clinical results after refixation of proximal hamstring tendon ruptures comparing different anchor systems]. / Klinische Ergebnisse nach Refixation proximaler Hamstring-Sehnen-Rupturen unter Berücksichtigung verschiedener Ankersysteme.

BACKGROUND: Injuries to the hamstring muscles and tendon complex are among the most frequent muscular injuries with proximal hamstring tendon avulsion being a particularly severe form. The surgical treatment of these injuries is superior to conservative management with respect to patient satisfaction, recovery of muscle strength and function as well as return to sport rates. It is therefore the method of choice. OBJECTIVE: Presentation and comparison of the surgical results after treatment with titanium, polyether ether ketone (PEEK) and all suture anchors. MATERIAL AND METHODS: A systematic search was carried out in the PubMed medical database and the results are summarized. RESULTS: All systems exhibit comparable biomechanical properties regarding elongation and ultimate failure load. Tendon repair with these anchors results in good to excellent clinical outcomes and shows high return to sport and low complication rates. Patient satisfaction after hamstring tendon repair is reported to be over 90% and return to sport rate is 80-100%. The muscle strength recovers to 80-90% in comparison to the contralateral side. CONCLUSION: All available anchors systems provide good to excellent clinical outcomes and an explicit advantage for one anchor system could so far not be shown.

The bone attachments of the medial collateral and posterior oblique ligaments are defined anatomically and radiographically.

PURPOSE: To define the bony attachments of the medial ligaments relative to anatomical and radiographic bony landmarks, providing information for medial collateral ligament (MCL) surgery. METHOD: The femoral and tibial attachments of the superficial MCL (sMCL), deep MCL (dMCL) and posterior oblique ligament (POL), plus the medial epicondyle (ME) were defined by radiopaque staples in 22 knees. These were measured radiographically and optically; the precision was calculated and data normalised to the sizes of the condyles. Femoral locations were referenced to the ME and to Blumensaat's line and the posterior cortex. RESULTS: The femoral sMCL attachment enveloped the ME, centred 1 mm proximal to it, at 37 ± 2 mm (normalised at 53 ± 2%) posterior to the most-anterior condyle border. The femoral dMCL attachment was 6 mm (8%) distal and 5 mm (7%) posterior to the ME. The femoral POL attachment was 4 mm (5%) proximal and 11 mm (15%) posterior to the ME. The tibial sMCL attachment spread from 42 to 71 mm (81-137% of A-P plateau width) below the tibial plateau. The dMCL fanned out anterodistally to a wide tibial attachment 8 mm below the plateau and between 17 and 39 mm (33-76%) A-P. The POL attached 5 mm below the plateau, posterior to the dMCL. The 95% CI intra-observer was ± 0.6 mm, inter-observer ± 1.3 mm for digitisation. The inter-observer ICC for radiographs was 0.922. CONCLUSION: The bone attachments of the medial knee ligaments are located in relation to knee dimensions and osseous landmarks. These data facilitate repairs and reconstructions that can restore physiological laxity and stability patterns across the arc of knee flexion.

Degenerative isolated cartilage defects of the patellofemoral joint are associated with more severe symptoms compared to trauma-related defects: results of the German Cartilage Registry (KnorpelRegister DGOU).

PURPOSE: The purpose of this study was to utilize data from the German Cartilage Registry (KnorpelRegister DGOU) to examine the hypothesis that degenerative cartilage defects of the patellofemoral joint are associated with more severe clinical symptoms compared to trauma-related defects. METHODS: All patients with isolated focal cartilage defects of the patellofemoral joint registered in the German Cartilage Registry until May 2017 were included in the study. Patients with previous surgery of the ipsilateral knee were excluded. Baseline data including etiology (traumatic, degenerative), size, location and ICRS grade of the cartilage defects as well as the duration of symptoms were analyzed. Clinical symptoms were evaluated by means of the numeric analog scale (NAS) for pain and the Knee injury and Osteoarthritis Outcome Score (KOOS). Group comparisons were performed using the Mann-Whitney-U test along with the Chi-squared test and Fisher's exact test. A bivariate correlation analysis and a multivariable linear regression analysis were performed to investigate the association between the defect characteristics and the clinical scores. RESULTS: A total of 423 patients (203 traumatic and 220 degenerative defects) were included. Isolated degenerative cartilage defects were found to have significantly more trochlear locations (28% vs. 18%; p = 0.006), significantly less ICRS grade 4 lesions (50% vs. 73%; p = 0.002) and a significantly smaller defect size [median 300 (IQR 105-400) vs. 300 (200-400) mm2] when compared to those from traumatic etiology. Traumatic defects showed significantly better KOOS-ADL [77 (60-90) vs. 69 (56-82); p = 0.005], KOOS-pain [69 (56-81) vs. 61 (47-75); p = 0.001] and NAS [2 (1-5) vs. 4 (1-6); p = 0.005] scores compared to degenerative defects. The correlation analysis revealed only weak correlations between the quantitative defect characteristics and clinical scores. CONCLUSIONS: Degenerative isolated cartilage defects in the patellofemoral joint are associated with more severe clinical symptoms in comparison to trauma-related defects. Additionally, they show a larger variance regarding their location with more trochlear defects. LEVEL OF EVIDENCE: III.

[Recurrent instability and instability arthropathy]. / Rezidivinstabilität und Instabilitätsarthropathie.

Capsulolabral reconstruction (Bankart repair) is recommended as the first line treatment in young and functionally demanding active patients with anteroinferior shoulder instability, due to the high tendency to recurrent dislocation. This has become established both for arthroscopic and open primary shoulder stabilization with good clinical outcome; nevertheless, recurrence of dislocation is reported in up to 25% of patients. Risk factors for failed surgery are patient (e.g. young age, male gender and contact sports) and surgery (e.g. primarily underestimated glenoid bone loss, Hill-Sachs lesion, non-treatment of bipolar defects or malpositioned anchors) related. In the management of recurrent instability, it is necessary to carry out a thorough clinical investigation in addition to extended diagnostics with X­ray and computed tomography. A second Bankart repair is only indicated in patients with low demands and without any glenoid bone loss. In the majority of patients, bony augmentation of the glenoid is necessary and realized by coracoid or iliac crest bone block transfer. The Latarjet procedure is biomechanically advantageous due to the additional sling effect of the conjoined tendons and both techniques show good clinical outcomes and a low recurrence rate. Furthermore, engaging Hill-Sachs lesions also require additional treatment. Remplissage of the infraspinatus muscle, iliac crest bone block transfer and partial joint replacement are viable options. A final consensus for treatment of Hill-Sachs lesions has yet to be defined. Dislocation arthropathy is an underestimated complication as a result of frequent recurrent dislocations. After development of dislocation arthropathy, patients reported a painful restriction of range of motion rather than instability. Arthroscopic arthrolysis and comprehensive arthroscopic management (CAM procedure) are possible joint-preserving treatment options.

[Fixation of bony avulsions of the posterior cruciate ligament by a suture-bridge™ technique]. / Refixation tibialer knöcherner Avulsionsverletzungen des hinteren Kreuzbandes in Fadenankertechnik.

OBJECTIVE: Anatomical reduction of bony avulsions of the posterior cruciate ligament (PCL) by a suture-bridge™ (Arthrex, Naples, FL, USA) technique to restore posterior knee stability. INDICATIONS: Acute bony tibial avulsions of the PCL and multifragmentary fractures. CONTRAINDICATIONS: Chronic condition of avulsion fractures or posterior instability, advanced knee osteoarthritis, high-grade soft tissue injury, infection. SURGICAL TECHNIQUE: Prone position, minimally invasive posterior medial approach, exposure and reduction of the bony fragment, positioning of the proximal suture-anchor (interfragment), suturing the PCL and knotting to achieve repositioning of the anterior part of the fragment, tighten both ends of the tape by two suture anchors distally to the PCL insertion to fix the posterior part of the fragment. POSTOPERATIVE MANAGEMENT: Knee extension brace with posterior tibial support for 6 weeks, 20 kg partial weight-bearing and restricted flexion up to 90° for 6 weeks, physiotherapy in prone position from the first postoperative day. Full weight bearing after x­ray and clinical control after 6 weeks. RESULTS: Since 2016, 6 cases of a bony avulsion of the PCL treated with this technique (mean age 38 years; range 17-60 years). Postoperative x­ray at 6 weeks showed no fragment dislocation and complete bone healing. Irritation due to the anchor material was not observed up to 6 months postoperatively. No wound healing problems, infections, thrombosis or arthrofibrosis observed. No revisions. According to a recent review comparing the open with an arthroscopic fracture treatment the arthroscopic treatment may lead to a slightly higher subjective and objective outcome. Interestingly, the rate of arthrofibrosis was slightly elevated in the arthroscopic group. Seven of 18 included studies describe a suture fixation in case of a comminuted fracture. Especially in these cases a suture-bridge ™ fixation seems to be reasonable.