Aims

In order to release the contracture band completely without damaging normal tissues (such as the sciatic nerve) in the surgical treatment of gluteal muscle contracture (GMC), we tried to display the relationship between normal tissue and contracture bands by magnetic resonance neurography (MRN) images, and to predesign a minimally invasive surgery based on the MRN images in advance.

Introduction. Fast track arthroplasty regimens require preservation of motor power to perform early rehabilitation and ensure early discharge (1). Commonly performed nerve blocks like femoral and Sciatic nerve blocks results in motor weakness thereby interfering with early rehabilitation and may also predispose to patient falls (2, 3). Hence, targeting the terminal branches of the femoral and sciatic nerves around the knee joint under ultrasound is an attractive strategy. The nerve supply of interest for knee analgesia are the terminal branches of the femoral nerve, the genicular branches of the lateral cutaneous nerve of thigh, obturator and sciatic nerves (4). Methods. We modified the performance of the adductor canal block and combined it with US guided posterior pericapsular injection and lateral femoral cutaneous nerve block to provide analgesia around the knee joint. The femoral artery is first traced under the sartorius muscle until the origin of descending geniculate artery and the block is performed proximal to its origin. A needle is inserted in-plane between the Sartorius and rectus femoris above the fascia lata and 5 ml of 0.5% ropivacaine (LA) is injected to block the intermediate cutaneous nerve of thigh. The needle is then redirected to enter the fascia of Sartorius to deliver an additional 5ml of LA to cover the medial cutaneous nerve of thigh following which it is further advanced till the needle tip is seen to lie adjacent to the femoral artery under the Sartorius to perform the adductor canal block with an additional 15–20 ml of LA to cover nerve to vastus medialis, saphenous nerve and posterior division of the obturator nerve (Fig 1). The lateral cutaneous nerve of thigh is optionally blocked with 10 ml of LA near the anterior superior iliac spine between the origin of Sartorius and tensor fascia lata (Fig 2). The terminal branches of sciatic nerve to the knee joint is blocked by depositing 25 ml of local anesthetic solution between the popliteal artery and femur bone at the level of femoral epicondyles (Fig 3). Results. The initial experience of the block performed on 10 patients reveal the median (IQR) block duration is noted to be around 20 (±6.5) hours. The median (IQR) pain scores in the first 24 postoperative hours ranged from 0 (±0.5) to 3 (±2.5) at rest and 1.5 (±3.5) to 5.5 (±1) on movement. All patients were successfully mobilized on the morning of the first postoperative day. Conclusion. Motor sparing from the blocks while providing adequate analgesia can be achieved by selectively targeting the sensory innervation of the knee joint. Future comparative studies are needed to evaluate the performance of the block against other modes of analgesia for knee arthroplasty

In the peripheral nervous system of rats, a wide-variety of toxins has been studied to selectively target neurons projecting through a particular nerve. We employed 54 adult male rats to create a neuroma-in-continuity and to evaluate the effect of the immunotoxin OX7-saporin to inhibit neuroma-in-continuity formation. Materials and Methods: The left common peroneal, tibial or sciatic nerves were crushed by one 10-second application of a microforceps. At 3 and 6 weeks after nerve crush, the respective nerve was cut distal to the site of nerve crush, and microinjection of 2 μl of natural saline or 2 μl of the OX7-saporin was done. In all nerve specimens of the control group and the saline-injection experimental subgroups, gross observation showed a thickened area at the site of nerve crush. Histology showed features consistent with a neuroma-in-continuity. In 11 of the 14 nerve specimens of the OX7-saporin injection experimental subgroups, gross observation showed a narrowed area at the site of nerve crush. Histology showed prevention of neuroma-in-continuity formation as seen by wiping out of almost all nerve fibers, leaving an empty tube encasing by connective tissue. This study supports the hypothesis that intraneural injection of the OX7-saporin may inhibit neuroma-in-continuity formation

Comparing the results of leaving a 15-mm nerve gap with those of interposition graft in the sciatic nerves of rats, Scherman et al of Sweden found no difference. We carried out a similar study on 10 blue monkeys to see if equivalent results were obtained in primates. We resected 15 mm of the radial nerve in the left brachium through an anterolateral approach. In five monkeys the nerve gap was bridged with an interposition nerve graft sutured with 8/0 Prolene(. In the other five, the gap was traversed by six longitudinal sutures of 6/0 Vicryl(, resulting in 12 strands. The upper limbs were immobilised in fibreglass casts for six weeks. After six months we killed the monkeys and harvested the nerve, which was evaluated histologically in terms of organisation at the repair site, fibrotic reaction at the repair site, and the ratio of number of axons proximal and distal to the repair site. With both techniques, axonal growth across the gap averaged about 70%. The longitudinal gap sutures had slightly poorer organisation, with more tissue reaction. Our results agree with Scherman et al’s findings that there is little difference in the results of the two methods, and suggest that a simple substrate will support nerve regeneration

Aims

The aim of this study was to investigate the safety and efficacy of 3D-printed modular prostheses in patients who underwent joint-sparing limb salvage surgery (JSLSS) for malignant femoral diaphyseal bone tumours.

As our understanding of hip function and disease improves, it is evident that the acetabular fossa has received little attention, despite it comprising over half of the acetabulum’s surface area and showing the first signs of degeneration. The fossa’s function is expected to be more than augmenting static stability with the ligamentum teres and being a templating landmark in arthroplasty. Indeed, the fossa, which is almost mature at 16 weeks of intrauterine development, plays a key role in hip development, enabling its nutrition through vascularization and synovial fluid, as well as the influx of chondrogenic stem/progenitor cells that build articular cartilage. The pulvinar, a fibrofatty tissue in the fossa, has the same developmental origin as the synovium and articular cartilage and is a biologically active area. Its unique anatomy allows for homogeneous distribution of the axial loads into the joint. It is composed of intra-articular adipose tissue (IAAT), which has adipocytes, fibroblasts, leucocytes, and abundant mast cells, which participate in the inflammatory cascade after an insult to the joint. Hence, the fossa and pulvinar should be considered in decision-making and surgical outcomes in hip preservation surgery, not only for their size, shape, and extent, but also for their biological capacity as a source of cytokines, immune cells, and chondrogenic stem cells.

Cite this article: Bone Joint Res 2020;9(12):857–869.

The April 2015 Research Roundup360 looks at: MCID in grip strength and distal radial fracture; Experiencing rehab in a trial setting; Electrical stimulation and nerve recovery; Molecular diagnosis of TB?; Acetabular orientation: component and arthritis; Analgesia after knee arthroplasty; Bisphosphonate-associated femoral fractures

Over recent years hip arthroscopic surgery has evolved into one of the most rapidly expanding fields in orthopaedic surgery. Complications are largely transient and incidences between 0.5% and 6.4% have been reported. However, major complications can and do occur. This article analyses the reported complications and makes recommendations based on the literature review and personal experience on how to minimise them.