Beneficial clinical effects but limited tissue quality following osteochondral repair with a cell-free multilayered nano-composite scaffold in the talus.

BACKGROUND: The treatment of larger osteochondral lesions of the talus remains an operative challenge. In addition to micro fracturing and osteochondral transplantation one promising strategy could be the operative repair with a cell-free multilayered nano-composite scaffold with the potential to regenerate bone and cartilage in one treatment. METHODS: In this prospective case series four consecutive patients who suffered from a single osteochondral lesion (≥1.5cm2) on the medial talus were enrolled. The repair potential of the implant was assessed using MRI based biochemical, compositional MR sequences (T2 mapping) as well as semi-quantitative morphological analyses (MOCART score) at 18 months follow-up after the surgery. The clinical outcome was determined at 6-, 12-, 18-, and 24 months follow-up by using the Ankle Disability Index and the AOFAS score. RESULTS: At 18 months after the surgery, the clinical outcome was significantly improved compared to the preoperative baseline. Global T2 relaxation times of the repair tissue were significantly increased compared to the healthy control cartilage. CONCLUSIONS: Osteochondral repair with a cell-free, biomimetic scaffold provides good clinical, short-term results. However, biochemical MR imaging provides strong evidence for limited repair tissue quality at 18 months after the implantation. LEVEL OF EVIDENCE: IV.

Successful osteoconduction but limited cartilage tissue quality following osteochondral repair by a cell-free multilayered nano-composite scaffold at the knee.

INTRODUCTION: The treatment of larger osteochondral lesions in the knee is still a clinical challenge. One promising strategy to overcome this problem could be surgical repair by using a cell-free multilayered nano-composite scaffold. METHOD: In this prospective cohort study eight consecutive patients which suffered from a single osteochondral lesion (≥1.5 cm(2)) on the femoral condyle were enrolled. The repair potential of the implant was assessed by using MRI based biochemical MR sequences (T2 mapping) as well as semi-quantitative morphological analyses (MOCART score) at 18 months after the surgery. The clinical outcome was determined at six, 12, 18, and 24 month follow ups by using IKDC, Tegner-Lysholm, and Cincinnati knee scores. RESULTS: Seven out of eight patients showed a complete integration of the scaffold into the border zone and five out of eight patients excellent or good subchondral ossification of the implant at 18 months following implantation. The surface of the repair tissue was found to be intact in all eight patients. T2 mapping data and the zonal T2 index significantly differed in the repair tissue compared to the healthy control cartilage (P < 0.001) which indicates a limited quality of the repair cartilage. The clinical outcome scores consistently improved during the follow up period without reaching statistical significance. CONCLUSIONS: Osteochondral repair by implanting the MaioRegen® scaffold provides a successful osteoconduction and filling of the cartilage defect. However there is evidence for a limited repair cartilage tissue quality at 18 months after the surgery.

Reliability of radiographic landmarks in medial patello-femoral ligament reconstruction in relation to the anatomical femoral torsion.

PURPOSE: Anatomically correct graft positioning at the femoral insertion site is a key factor in surgical reconstruction of the medial patello-femoral ligament (MPFL). Basically there are two techniques to define this point in fluoroscopy during surgery. The role of the anatomical femoral torsion on the accuracy and reproducibility of both procedures has not been clarified. METHODS: Twenty human anatomical leg specimens were dissected. The femoral insertion of the MPFL was marked by two K-wires. The position of the ligament insertion was determined fluoroscopically in the true lateral view as used in routine clinical practice. The anatomical MPFL insertion was compared to the radiographic landmarks which were recommended by two previous studies. The anatomical femoral torsion of the specimens was assessed by computed tomography scans. RESULTS: In true lateral view fluoroscopy, the mean distance of the femoral MPFL insertion was -0.2 mm distal to the vertical reference line intersecting the posterior point of Blumensaat's line. In the anteroposterior direction, the mean distance was -2.0 mm posterior to the femoral cortex reference line. There was no correlation between anatomical femoral torsion and the distance of the femoral MPFL insertion to the posterior cortex. CONCLUSIONS: The results of this study strongly recommend use of a vertical line intersecting the most posterior point of Blumensaat's line as a reference to identify the MPFL insertion in the craniocaudal direction. In the anteroposterior direction, the femoral MPFL insertion showed distinctive variation and was found -2.0 mm posterior to the femoral cortex reference line without being influenced by the anatomical femoral torsion.

Arthroscopically assisted rotator cuff repair.

PURPOSE: The purpose of this study is to analyze the technique and value of arthroscopically assisted rotator cuff repair based on follow-up results after 3 years. TYPE OF STUDY: Case series. METHODS: Since the beginning of 1997, 216 patients included in a clinical case series at the Department of Trauma Surgery of the Hospital of the Barmherzigen Brüder Eisenstadt have undergone arthroscopically assisted rotator cuff repair. Radiographic, clinical, and intraoperative parameters were carefully documented. All patients were treated with an arthroscopically assisted transosseous technique, in which bone tunnels are drilled with a target drill unit through the humeral head lateral to the biceps tendon from a third ventrocaudal incision on the humerus. The nonresorbable sutures placed into the cuff with a suture punch are passed transosseously and tied in the incision directly on the humeral head using a knot pusher. In December 2000, 84 patients (average age, 54.8 years; range, 28 to 74 years) underwent a clinical follow-up evaluation after a mean follow-up time of 35 months (28 to 44 months). RESULTS: The average Constant score improved from a preoperative rating of 44.9 to a postoperative rating of 87.2. University of California, Los Angeles score was improved from 11.3 to 31.1 ( P <.001). Time of preoperative history, tear size, and condition of the long biceps tendon were found to have significant influence on results (P <.05). Thus, 20 patients with chronic, untreated tears of the long biceps tendon showed significantly worse results with a score of 81.8. Patients with curved or hooked acromion types (Bigliani II and III) showed significantly better results (P <.05) and patients with extensive tears had significantly worse results because of a residual strength deficit. The essential determinant was achievement of a stable tear closure with arthroscopic verification and documentation. Thus, 8 patients with a documented small gap between repaired cuff and bone showed a significantly worse rating in the Constant score, with 80.5 (P <.05). The complications encountered included development of seroma in one case and one case with frozen shoulder symptoms. CONCLUSIONS: Arthroscopically assisted repair of the rotator cuff was shown to be an effective procedure, guaranteeing good clinical results for medium- and large-sized tears with adequate mobility. Advantages include a primary stability comparable to that seen with open repair. Minimized trauma to soft tissue is associated with a lesser degree of postoperative pain and scarring and reduced hospitalization. LEVEL OF EVIDENCE: Level IV, case series.

Arthroscopic reconstruction of anterior cruciate ligament using BTB patellar ligament in the press-fit technique.

Arthroscopic reconstruction of the anterior cruciate ligament (ACL) with a bone-patellar tendon-bone graft in the press-fit technique is an efficient procedure, which provides high primary stability without use of implants and thus ensures early functional rehabilitation. The procedure is based on graft harvest with an oscillating hollow saw, which allows collection of cylindrical bone blocks. Femoral fixation using a template and file has been standardized to an extent that ensures secure press-fit fixation. Tibial anchorage is achieved by refilling the tibial tunnel with the bone cylinder removed previously. Primary stability is at least equivalent to that achieved with interference screw or staple fixation, and has been evaluated in a pull-out study in ovine knees. Two major problems encountered with revision procedures--metal removal or tunnel enlargement--may be avoided effectively. In a prospective study of 32 patients, postoperative computed tomography (CT) evaluation after three months showed presence of cancellous bone material inserted into the tibial tunnel. Postoperative tunnel enlargement seen frequently with other procedures can be avoided in almost all knees. Revision procedures after press-fit fixation can be done without problems. This procedure provides a cost-efficient alternative for reconstruction of the ACL, because it does not require implants.