Osteointegration of soft tissue grafts within the bone tunnels in anterior cruciate ligament reconstruction can be enhanced

Anterior cruciate ligament reconstruction with a soft tissue autograft (hamstring autograft) has grown in popularity in the last 10 years. However, the issues of a relatively long healing time and an inferior histological healing result in terms of Sharpey-like fibers connection in soft tissue grafts are still unsolved. To obtain a promising outcome in the long run, prompt osteointegration of the tendon graft within the bone tunnel is essential. In recent decades, numerous methods have been reported to enhance osteointegration of soft tissue graft in the bone tunnel. In this article, we review the current literature in this research area, mainly focusing on strategies applied to the local bone tunnel environment. Biological strategies such as stem cell and gene transfer technology, as well as the local application of specific growth factors have been reported to yield exciting results. The use of biological bone substitute and physical stimulation also obtained promising results. Artificially engineered tissue has promise as a solution to the problem of donor site morbidity. Despite these encouraging results, the current available evidence is still experimental. Further clinical studies in terms of randomized control trial in the future should be conducted to extrapolate these basic science study findings into clinical practice. © 2009 Springer-Verlag.postprin

Intraosseous foreign body granuloma in rotator cuff repair with bioabsorbable suture anchor

Biodegradable implants lead to problems such as cyst formation, soft-tissue inflammation, loose implant fragments or local osteolysis. This report represents the first published case of an intraosseous foreign body granuloma in the humeral head after arthroscopic rotator cuff tear fixation with a poly-l-lactide (PLLA) suture anchor. A 48-year-old female patient presented with pain in her right shoulder. A refixation of her right supraspinatus tendon with a biodegradable suture anchor was performed 11 months ago at an external hospital. Laboratory tests showed normal values for C-reactive protein, leukocytes and the erythrocyte sedimentation rate. No signs of infection or instability were noted. The visual analogue scale (VAS) was 8, the simple shoulder test (SST) was 4 and the American shoulder and elbow surgeons score (ASES) was 44. Plain radiographs showed high lucency in the area of the tuberculum majus. MRI showed an intra- and extraosseous mass surrounded by fluid in this area. Surgical care involved arthroscopic debridement and removal of the suture anchor. Histological examination revealed a foreign body granuloma. At the 18-month follow-up the patient was nearly pain-free. The VAS was 2, SST was 10 and ASES was 88. Foreign body granulomas are a well known but rarely described complication that arises after the use of biodegradable suture anchors in shoulder surgery. Every patient presenting with shoulder pain after usage of a biodegradable fixation material should be evaluated closely. Orthopaedic surgeons should be aware of the possibility of delayed foreign body reactions, especially after using PLLA anchors

Comparative evaluation of the tendon-bone interface contact pressure in different single- versus double-row suture anchor repair techniques

The aim of the study was to evaluate the time zero contact pressure over a defined rotator cuff footprint using different repair and stitch techniques in an established sheep model. Forty fresh-frozen sheep shoulders were randomly assigned to five repair groups: single-row repair using simple stitches (SRA-s), single-row repair using horizontal mattress stitches (SRA-m), and single-row repair using arthroscopic Mason-Allen stitches (SRA-ama). Double-row repair was either performed with a combination of simple and horizontal mattress stitches (DRA-sm) or with arthroscopic Mason-Allen/horizontal mattress stitches (DRA-amam). Investigations were performed using a pressure-sensitive film system. The average contact pressure and pressure pattern were measured for each group. Contact pressure was lowest in SRA-m followed by SRA-s. SRA-ama showed highest contact pressure of all single-row treatment groups (P < 0.05). DRA-amam presented the highest overall contact pressure (P < 0.05), whereas DRA-sm exerted contact pressure equal to that of SRA-ama. Both double-row techniques showed the most expanded pressure pattern. Average contact pressures for the more complex single- and double-row techniques utilizing arthroscopic Mason-Allen stitches were greater than were those of the repair techniques utilizing simple and horizontal mattress stitches. However, the contact pattern between the anchors could be increased by using the double-row technique, resulting in more footprint coverage compared to patterns utilizing the single-row techniques. These results support the use of the more complex arthroscopic Mason-Allen stitches and may improve the environment for healing of the repaired rotator cuff tendon

Role of high tibial osteotomy in chronic injuries of posterior cruciate ligament and posterolateral corner

High tibial osteotomy (HTO) is a surgical procedure used to change the mechanical weight-bearing axis and alter the loads carried through the knee. Conventional indications for HTO are medial compartment osteoarthritis and varus malalignment of the knee causing pain and dysfunction. Traditionally, knee instability associated with varus thrust has been considered a contraindication. However, today the indications include patients with chronic ligament deficiencies and malalignment, because an HTO procedure can change not only the coronal but also the sagittal plane of the knee. The sagittal plane has generally been ignored in HTO literature, but its modification has a significant impact on biomechanics and joint stability. Indeed, decreased posterior tibial slope causes posterior tibia translation and helps the anterior cruciate ligament (ACL)-deficient knee. Vice versa, increased tibial slope causes anterior tibia translation and helps the posterior cruciate ligament (PCL)-deficient knee. A review of literature shows that soft tissue procedures alone are often unsatisfactory for chronic posterior instability if alignment is not corrected. Since limb alignment is the most important factor to consider in lower limb reconstructive surgery, diagnosis and treatment of limb malalignment should not be ignored in management of chronic ligamentous instabilities. This paper reviews the effects of chronic posterior instability and tibial slope alteration on knee and soft tissues, in addition to planning and surgical technique for chronic posterior and posterolateral instability with HTO