Journal of Musculoskeletal Research

The incidence of dislocation after primary THR has been quoted up to 2.25%, and between 2% and 20% for revision THR. We report clinical and radiological findings in 76 patients treated with a constrained liner for those considered at high-risk for dislocation, intraoperative instability or recurrent dislocations. Mean follow up was 12 months. Post operatively there were two cases of recurrent dislocation, one aseptic loosening and nine cases of deep infection. These results support that these liners have been used to treat, or in some cases prevent, instability after total hip replacement.

Objectives: Avascular necrosis (AVN) of the femoral head is a pathologic process resulting from interruption of blood supply to bone. The aim of this paper is to describe the technical aspects and outcome of a modified technique of core decompression and bone graft injection for the treatment of AVNFH. Methods: A total of 20 patients (26 femoral head AVN) Ficat stage I to early III were treated using core decompression kit followed by injection with bone graft material. Nine hips were stage III, 16 stage II and 1 stage I. Average operative time was 25min. Results: At a median follow-up of 48 months, 20 hips (77%) had almost complete pain relief while pain persisted in 6 hips (23%). All patients who demonstrated clinical response exhibited radiological stabilization of disease. The mean Harris hip score for all patients’ prior and following surgery were 41 and 85, respectively ($p<0.0001$). Conclusions: Femur head decompression using core decompression kit followed by bone substitute injection can result in long-term pain relief and prevent progression of AVN in the majority of patients.

Purpose: The purpose of this study is to examine the outcomes of a cohort of patients who have undergone a new surgical technique for anterior cruciate ligament (ACL) tunnel targeting using the footprint of the torn ACL as soft tissue markers. This is in the setting of anatomical ACLR with remnant preservation. Methods: This retrospective single center cohort study was conducted on patients undergoing a primary ACLR between August 2008 and February 2013. A total of 103 patients underwent ACLR with a remnant sparing technique with non-radiological soft tissue targeting of femoral and tibial tunnels. Exclusion criteria included skeletal immaturity, concomitant meniscal repair or ligament surgery, knee malalignment, delayed presentation ($>$6 months post injury) and incomplete medical insurance. At 2 years all patients had gadolinium MRI scan, plain film X-ray, and a clinical assessment including KT-1000 arthrometry, and the following outcome scores; Tegner, IKDC (subjective/objective), Lysholm, Cincinnati and ACL Quality of Life. Results: A total of 44 patients (18 males, 26 females; mean age 30.9 years $+$/$-$11.8) were enrolled within the study. About 93.2% of the participants achieved an IKDC objective rating of A or B. The mean scores for outcome measures were; IKDC Subjective (84.9$+$/$-$11), Tegner (6.1$+$/$-$2), Lysholm (87.2$+$/$-$11.3), Cincinnati (358.1$+$/$-$40.8) and ACL Quality of Life (75.4$+$/$-$19). There were no graft failures at follow up. No patients had a loss of full extension $>5^{\circ }$. All tunnels were positioned satisfactorily. Almost half of all femoral tunnels (47.8%) and 30.4% of tibial tunnels were confluent at the joint surface. Conclusions: This series demonstrates that anatomical double tunnel ACLR using non-radiological guided remnant retention technique, provides satisfactory 2-year clinical outcomes and is a safe and effective option. Targeting tunnels to be within the native remnant leads to high rates of tunnel confluence.

Background: Knee traumata are associated with arthrogenic muscle inhibition (AMI). We aimed to identify impact factors on AMI. Methods: A total of 37 patients with meniscus injuries were interviewed and examined for maximum isometric knee extensor force preoperatively. We analyzed AMI as relative maximum isometric force between healthy and injured legs. Regression analyses were computed to evaluate associations between an AMI with muscle-strength reduction $>25$% and several parameters and between cartilage damage$>$stadium 3 and several parameters. ROC curves were calculated to investigate effectiveness of age and pain at rest for prediction of cartilage lesions $>$stadium 3. Results: Meniscus injuries lead to distinct AMI with reduced strength of 26.6% in mean. In multi-variate logistic regressions, an AMI with muscle weakness $>25$% was associated with higher severity of cartilage lesions (OR3.267, 95% CI 1.059–10.078, $p=0.0394$). In uni-variate regression analyses, pain at rest (OR1.398, 95%CI 1.071–1.824, $p=0.0137$) and patients’ age (per year) (OR1.145, 95%CI 1.042–1.257, $p=0.00488$) were associated with cartilage damage$>$stadium 3. Optimal cut-off values for patients’ age and pain at rest to predict cartilage damage stadium$>3$ were 44.5 years and VAS-scale-value 4.5 with good effectiveness (AUC 0.855 and 0.732), respectively. Conclusions: Meniscus injuries lead to distinct AMI with 26.6% reduction in muscle strength. Concomitant cartilage damage is an important cofactor for development of distinct AMI. Moderate to severe pain at rest and age $>44.5$ years were indicators for concomitant higher cartilage damage in patients with meniscal lesions.

Objective: The present study was designed to investigate the effects of platelet rich plasma (PRP) and autograft-human PRP on bone healing in a rat model. Methods: A critical sized defect at least twice as long as the diameter of the diaphysis was made in 16 rats to create a non-union model. The defect was either supplied with hPRP, or autograft-hPRP (experimental groups) and autograft (positive control) or left empty (negative control). Radiographs of each forelimb was taken postoperatively on the 1st day and then at the 35th, and 56th days post-injury to evaluate bone formation, union and remodeling of the defect. The operated radiuses were removed on 56th post-operative day and were evaluated biomechanically, histopathologically and ultrastructurally by scanning electron microscopy. Results: There was significant difference ($p<$0.05) between the groups in union and cancellous bone so that the autograft, autograft-hPRP and hPRP groups were significantly ($p<$0.05) superior to the empty group and in cortical bone formation the autograft-PRP group was significantly ($p<$0.05) superior to the other three groups but there was no significant difference ($p>$0.05) between the groups in cortical bone marrow. Biomechanical evaluation did not show any significant differences. There was no significant difference ($p>$0.05) between the groups in radiological parameters at 35th and 56th post-operative days. Conclusion: This study demonstrated that autograft-hPRP is most effective and could promote bone regeneration in the critical sized defects in rat model.

Congenital absence of the long head of biceps tendon (LHBT) is a very rare entity. With its debatable role in shoulder stability, the literature provides few reports of absent LHBT and its association with shoulder instability or pain. Reports of instability are associated with labral tear or attenuation of glenohumeral ligaments. We are first time reporting a case of congenital absence of the LHBT and associated bony Bankart’s lesion and posterior labral tear.