Christian Ossendorf

Autologous chondrocyte implantation (ACI) for the treatment of large and complex cartilage lesions of the knee

BackgroundComplex cartilage lesions of the knee including large cartilage defects, kissing lesions, and osteoarthritis (OA) represent a common problem in orthopaedic surgery and a challenging task for the orthopaedic surgeon. As there is only limited data, we performed a prospective clinical study to investigate the benefit of autologous chondrocyte implantation (ACI) for this demanding patient population.MethodsFifty-one patients displaying at least one of the criteria were included in the present retrospective study: (1.) defect size larger than 10 cm2; (2.) multiple lesions; (3.) kissing lesions, cartilage lesions Outerbridge grade III-IV, and/or (4.) mild/moderate osteoarthritis (OA). For outcome measurements, the International Cartilage Societys International Knee Documentation Committees (IKDC) questionnaire, as well as the Cincinnati, Tegner, Lysholm and Noyes scores were used. Radiographic evaluation for OA was done using the Kellgren score.Results and DiscussionPatients age was 36 years (13-61), defects size 7.25 (3-17.5) cm2, previous surgical procedures 1.94 (0-8), and follow-up 30 (12-63) months. Instruments for outcome measurement indicated significant improvement in activity, working ability, and sports. Mean ICRS grade improved from 3.8 preoperatively to grade 3 postoperatively, Tegner grade 1.4 enhanced to grade 3.39. The Cincinnati score enhanced from 25.65 to 66.33, the Lysholm score from 33.26 to 64.68, the Larson score from 43.59 to 79.31, and Noyes score from 12.5 to 46.67, representing an improvement from Cincinnati grade 3.65 to grade 2.1. Lysholm grade 4 improved to grade 3.33, and Larson grade 3.96 to 2.78 (Table 1), (p < 0.001). Patients with kissing cartilage lesions had similar results as patients with single cartilage lesions.Table 1Mean scores and grades at surgery (Tx) and at follow-upTxFollow-upScoreGradeScoreGradeICRS43Tegner13Noyes1347Cincinnati264662Lysholm334653Larson444793ConclusionOur results suggest that ACI provides mid-term results in patients with complex cartilage lesions of the knee. If long term results will confirm our findings, ACI may be a considered as a valuable tool for the treatment of complex cartilage lesions of the knee.

Posterior screw fixation in rotationally unstable pelvic ring injuries.

OBJECTIVE Although the stability of the pelvic ring primarily depends on the integrity of the posterior sacroiliac arch, lateral compression fractures with rotational instability are commonly treated by anterior fixation alone. The objective of the present study was to assess the outcome of patients with these fractures treated by posterior iliosacral screw fixation alone. METHODS Patients with rotationally unstable lateral compression fractures of the pelvic ring (Young and Burgess LC I and LC II or AO/Tile B2) treated by percutaneous iliosacral fixation alone were included. Postoperative complications, need for secondary surgery, malunion, secondary fracture displacement and the time to full-weight bearing were documented. RESULTS Twenty-five patients (13 female, 26 male; age: 56±20 years) were treated by percutaneous screw fixation (14 bilaterally, 11 unilaterally). Mean follow-up was 6±4 months, mean time to full weight bearing 9±3 weeks. Revision surgery was necessary in two patients (8%) due to nerve irritation; an additional anterior stabilisation was needed in two other patients (8%) due to secondary dislocation. Wound infection or motor weakness were not encountered, non-union of the posterior arch did not occur. Non-union of the pubic rami, however, occurred in two patients. The presence of malunion of the pubic rami did not affect the time to full weight bearing. CONCLUSIONS Percutanous iliosacral screw fixation alone is a sufficient technique for the stabilisation of rotationally unstable pelvic fractures with low rates of complications or non-unions. It allows for a minimally invasive treatment thus being a useful option in patients who do not qualify for open anterior fixation.

Osteoblastic and Osteolytic Human Osteosarcomas can be Studied with a new Xenograft Mouse Model Producing Spontaneous Metastases

There is no animal model that reflects the histological and radiographical heterogeneity of osteosarcoma. We assessed seven osteosarcoma cell lines for their potential to develop orthotopic tumors and lung metastasis in SCID mice. Whereas radiologically, 143B developed osteolytic tumors, SaOS-LM7 developed osteoblastic primary tumors. The mineralization status was confirmed by assessing the alkaline phosphatase activity and the microarray expression profile. We herein report a xenograft orthotopic osteosarcoma mouse model to assess osteoblastic and osteolytic lesions, which may contribute in the search for new diagnostic and therapeutic approaches.

Vertebral Body Stenting Versus Kyphoplasty for the Treatment of Osteoporotic Vertebral Compression Fractures A Randomized Trial

BACKGROUND In the treatment of vertebral compression fractures, vertebral body stenting with an expandable scaffold inserted before application of the bone cement was developed to impede secondary loss of vertebral height encountered in patients treated with balloon kyphoplasty. The purpose of this study was to clarify whether there are relevant differences between balloon kyphoplasty and vertebral body stenting with regard to perioperative and postoperative findings. METHODS In a two-armed randomized controlled trial, patients with a total of 100 fresh osteoporotic vertebral compression fractures were treated with either balloon kyphoplasty or vertebral body stenting. The primary outcome was the post-interventional change in the kyphotic angle on radiographs. The secondary outcomes were the maximum pressure of the balloon tamp during inflation, radiation exposure time, perioperative complications, and cement leakage. RESULTS The mean reduction (and standard deviation) of kyphosis (the kyphotic correction angle) was 4.5° ± 3.6° after balloon kyphoplasty and 4.7° ± 4.2° after vertebral body stenting (p = 0.972). The mean pressures were 24 ± 5 bar (348 ± 72 pounds per square inch [psi]) during vertebral body stenting and 16 ± 6 bar (233 ± 81 psi) during balloon kyphoplasty (p = 0.014). There were no significant differences in radiation exposure time.None of the patients underwent revision surgery, and postoperative neurologic sequelae were not observed. Cement leakage occurred at twenty-five of the 100 vertebral levels without significant differences between the two intervention arms (p = 0.230). Intraoperative material-related complications were observed at one of the fifty vertebral levels in the balloon kyphoplasty group and at nine of the fifty levels in the vertebral body stenting group. CONCLUSIONS No beneficial effect of vertebral body stenting over balloon kyphoplasty was found among patients with painful osteoporotic vertebral fractures with regard to kyphotic correction, cement leakage, radiation exposure time, or neurologic sequelae. Vertebral body stenting was associated with significantly higher pressures during balloon inflation and more material-related complications.

Subacromial pressures vary with simulated sleep positions

HYPOTHESIS Subacromial impingement is one of the underlying factors of rotator cuff pathologies and is linked to increased subacromial pressures. Because humans spend about one-third of their life sleeping, we hypothesized that distinct shoulder positions while sleeping may considerably influence nocturnal subacromial pressures. Consequently, atrophy and rupture can affect tendon healing after rotator cuff repair, thus potentially discrediting the outcome of surgery. MATERIALS AND METHODS We determined the subacromial pressures acting on the rotator cuff in the 4 most common sleep positions and related these pressures to the mean arterial blood pressure and physical examination findings in 20 healthy volunteers. RESULTS Subacromial pressures were significantly lower in participants sleeping preferably in a supine position than in participants sleeping in side or prone positions (P < .005). DISCUSSION As tendon perfusion is crucial for tendon-to-bone healing during postoperative physical therapy after rotator cuff reconstruction and for prevention of additional damage to healthy or already torn cuffs, potential clinical relevance may emerge from the present study. CONCLUSION Distinct shoulder positions considerably influence subacromial pressures. Our findings may be considered in physiotherapeutic concepts after rotator cuff surgery.

Avulsion Fracture of the Dorsal Talonavicular Ligament: A Subtle Radiographic Sign of Possible Chopart Joint Dislocation:

Level of Evidence: V, Expert Opinion

Traumatic atlantoaxial rotatory subluxation in an adolescent: a case report

IntroductionAtlantoaxial rotatory subluxation is rarely caused by trauma in adults. Usually, the treatment of choice is traction using Halo/Gardner-Wells fixation devices for up to six weeks.Case presentationWe present the case of a 19-year-old Caucasian woman with traumatic atlantoaxial subluxation. Early reduction three hours after trauma and immobilization using only a soft collar were performed and yielded very good clinical results.ConclusionIn the adult population, atlantoaxial subluxation is a rare condition but is severe if untreated. Early treatment implies a non-surgical approach and a good outcome. Conservative treatment is the recommended first step for this condition.

Surgical Stabilization of Postpartum Symphyseal Instability: Two Cases and a Review of the Literature

During pregnancy, asymptomatic widening of the symphysis pubis by about one third is normal and considered physiological. However, peripartal relaxation of the symphyseal and sacroiliac ligaments may cause significant complaints conditions including pain and gait dysfunction. Usually, patients are treated by the application of pelvic binders and bed rest up to several weeks. Surgical stabilization is performed seldom, though it may be promising in selected patients. Based on 2 cases of postpartum symphyseal instability treated by surgical fixation, the current literature was reviewed systematically to evaluate the outcome and potential complications of surgical fixation of symphyseal instability. Thirteen articles met inclusion criteria and were analyzed in detail. Including the two cases presented, surgical stabilization of postpartum symphyseal instability has been described for 33 patients. In conclusion, though only based on case reports and case series, early surgical stabilization represents a decent treatment option for postpartum symphyseal instability and may be indicated by pain or walking disability alone. In regard to the clinical outcome comparing internal and external fixation, no differences were demonstrable. However, the rate of infection was higher in patients treated by external fixation. Based on these data, we propose a treatment algorithm for this injury.

A New Incision Technique to Reduce Tibiofemoral Mismatch in Rotationplasty

Rotationplasty provides stable and durable biologic reconstruction after tumor resection around the knee and renders reliable results, in young patients. However, after resection of the tumor, there is often a mismatch between the circumference of the proximal (femoral) and the distal (tibial) parts. Because rotationplasty includes an intercalary amputation where the ends are readapted, there is always a mismatch of the proximal and distal circumferences of the soft tissue envelope. To facilitate skin closure without tension and to avoid impaired wound healing and subsequent infections, the type of incision is critical and must be carefully planned. We present a new incision technique for rotationplasty about the knee. Half of the difference of the incision length of the proximal and distal circumferences represents the base of the triangle proximally, medially and laterally of the thigh. After adapting both ends, the peak of this flat triangle is distally adapted via a vertical incision which allows it to match unequal circumferences. This technique was used in eight patients, in all of whom the wounds healed uneventfully.

Is the internal rotation lag sign a sensitive test for detecting hip abductor tendon ruptures after total hip arthroplasty

IntroductionTotal hip arthroplasty (THA) is one of the most frequently performed procedures in orthopaedics and weakness of external rotators is often recognized thereafter. However, the etiology of lateral hip pain is multifaceted. For the diagnosis of abductor tendon rupture, magnetic resonance imaging (MRI) is the gold standard. As not every patient can be subjected to MRI, a clinical diagnostic test for easy detection of lesions of the abductor tendon is missing. Here, we present the internal rotation lack sign indicating abductor tendon pathology.MethodsThe patient is placed in lateral position on a stretcher with hips and knees in neutral position. The knee is flexed to 45° and the hip passively abducted and elevated by the investigator. With the foot passively abducted, the patient is then asked to bring his knee in direction to the examination table. This motion is also tested passively. The test is regarded positive, if no internal rotation is possible and/or if this is painful. If groin pain is elicited during either of the exercises, the test is also rated positive.ResultsWe evaluated this test in 20 patients clinically and by magnetic resonance imaging (MRI). All patients demonstrated a positive internal rotation lag sign. Twelve of them lag of internal rotation and evidence of anterior abductor tendon rupture on MRI, 8 with lag of internal rotation and no evidence of abductor tendon rupture.ConclusionThe new clinical diagnostic sign presented here may improve the diagnosis of abductor tendon rupture in the future.Level of Evidence: Diagnostic study, level I.