Hyperextension injuries of the knee: do patterns of bone bruising predict soft tissue injury?

OBJECTIVE: To establish whether patterns of soft tissue injury following knee hyperextension are associated with post-traumatic 'bone bruise' distribution. MATERIALS AND METHODS: Patients with a knee MRI within one year of hyperextension injury were identified at our institution over a 7 year period. MRIs, plain radiographs and clinical details of these patients were reviewed. RESULTS: Twenty-five patients were identified (median time from injury to MRI = 24 days). The most common sites of bone bruising were the anteromedial tibial plateau (48%) and anterolateral tibial plateau (44%). There were high rates of injury to the posterior capsule (52%), ACL (40%) and PCL (40%) but lower rates of injury to the menisci (20%), medial and lateral collateral ligaments (16%) and posterolateral corner (16%). Anterior tibial plateau oedema and rupture of the posterior capsule predicted cruciate ligament injury [OR = 10.5 (p = 0.02) and 24.0 (p = 0.001) respectively]. Whilst anterolateral tibial plateau oedema strongly predicted PCL injury [OR = 26.0, p = 0.003], ACL injury was associated with a variable pattern of bone bruising. Meniscal injury was unrelated to the extent or pattern of bone bruising. 5 out of 8 patients with a 'double sulcus' on the lateral radiograph had ACL injury. The presence of a double sulcus showed significant association with anteromedial kissing contusions (OR = 7.8, p = 0.03). CONCLUSIONS: Following knee hyperextension, bone bruising patterns may be associated with cruciate ligament injury. Other structures are injured less frequently and have weaker associations with bone bruise distribution. The double sulcus sign is a radiographic marker that confers a high probability of ACL injury.

The use of MRI to detect occult fractures of the proximal femur: a study of 102 consecutive cases over a ten-year period.

An MR scan was performed on all patients who presented to our hospital with a clinical diagnosis of a fracture of the proximal femur, but who had no abnormality on plain radiographs. This was a prospective study of 102 consecutive patients over a ten-year period. There were 98 patients who fulfilled our inclusion criteria, of whom 75 were scanned within 48 hours of admission, with an overall mean time between admission and scanning of 2.4 days (0 to 10). A total of 81 patients (83%) had abnormalities detected on MRI; 23 (23%) required operative management. The use of MRI led to the early diagnosis and treatment of occult hip pathology. We recommend that incomplete intertrochanteric fractures are managed non-operatively with protected weight-bearing. The study illustrates the high incidence of fractures which are not apparent on plain radiographs, and shows that MRI is useful when diagnosing other pathology such as malignancy, which may not be apparent on plain films.

Flexor tenorrhaphy tensile strength: reduction by cyclic loading: in vitro and ex vivo porcine study.

The integrity of the repair is critical to maintain coaptation of the severed flexor tendon end until healing has advanced sufficiently. In our hospital, we use a modified Savage repair (four-strand Adelaide technique) using 3-0 Ethibond (Ethicon, Somerville, NJ, USA) for acute flexor tenorrhaphy and an active postrepair mobilization protocol. To explain the apparent differences between the theoretical and actual repair strength of a multistrand repair in a single tension test and the reduced strength of a repair subjected to cyclic loading, we compared single and cyclical tensile loading with different suture in vitro configurations of 3-0 Ethibond (Ethicon, Somerville, NJ, USA; one, two, and four strands) and an ex vivo four-strand repair of freshly divided porcine tendon to calculate the ultimate tensile strength (UTS). Mechanical testing was repeated 15 times with both single tensile and cyclical loading for each suture configuration and porcine repair. In the in vitro model, the presence of a knot in a single strand reduced the UTS by 50%. The stiffness of a knotted strand was substantially less than the unknotted strand but became identical after cyclical loading. There was no statistical significance of the UTS between single and cyclical loading with different numbers of strands in this model. In the ex vivo four-strand porcine repair model, there was a significant reduction in UTS with cyclical loading, which equated to the number of strands times the strength of the knotted strand. This discrepancy can be explained by the change in stiffness of the knotted strand after cyclical loading and has important implications for previous studies of suture tendon repair using single tensile loading where the UTS may have been overestimated. We believe that cyclical loading is more representative of physiological loading after acute flexor tendon repair and should be the testing model of choice in suture tenorrhaphy studies.

Medium-to-long term DEXA analysis of an uncemented (AML) femoral component.

We present medium-to-long-term bone mineral density studies assessing bone resorption and remodelling around the cementless femoral component of a total hip arthroplasty (Depuy AML prosthesis). Bone mineral densities were compared with the unoperated side at a time interval of eight years between scans using dual energy X-ray absorptiometry. Initial proximal stress shielding is known but we show that this response continues into the medium to long term in relative terms. We have also found an overall trend for bone mineral density to increase around the prosthesis with the greatest changes occurring distally. The greatest real increase in bone mineral density occurred in Gruen zones 2, 3 and 5 with smaller increases in zones 1, 4, 6 and 7. However, when compared with the contralateral unoperated femur (thus considering systemic changes in bone mineral density), we found these changes only reached statistical significance in Gruen zones 5, 6 and 7.

Medium-term dexa analysis of an uncemented femoral component.

We investigated the bone remodelling around the AML uncemented femoral component using DEXA analysis and plain radiography in 19 patients at a mean of 89 months from operation. All patients had previously been analysed at a mean of 32 months after surgery. We found a decrease in bone mineral density around the AML implant between the two scans in Gruen zones 1,2 and 6 of up to 8%, but an increase in zones 4,5 and 7 of up to 36%. The increase in zones 4 and 5 were statistically significant (P>0.05). The relative difference between the operated and unoperated hips also showed a reduction in the bone density ratio with time, except in zones 4 and 5 where an increase was seen. We confirm the results of previous studies of proximal stress shielding and distal loading around the AML implant and demonstrate that bone remodelling continues in the medium term. (Hip International 2004; 14: 182-8).

Long-term results of arthroscopic synovectomy for seropositive rheumatoid arthritis: 6-16 year review.

We prospectively studied a consecutive series of 25 knees (21 patients) treated with arthroscopic synovectomy for seropositive rheumatoid arthritis. All patients had pain and swelling and were in the early stages of the disease process (Larsen grade 2 or less). Three patients were lost to follow-up. At a mean of 8 years from operation two knees underwent total knee replacement with another two knees required a further arthroscopic synovectomy. One patient continued to experience intermittent mild synovitis. The range of movement was maintained or improved by surgery in 73% of cases but radiological evidence of degenerative change was seen in all knees. We discuss the technical difficulties associated with arthroscopic synovectomy that were associated with a small complication rate. In appropriately selected patients unresponsive to medical therapy, arthroscopic synovectomy can give safe and reliable results.

Cryotherapy compared with Robert Jones bandage after total knee replacement: a prospective randomized trial.

Sixty patients undergoing total knee replacement were randomized to receive either a cold compression dressing (Cryo/Cuff, Aircast, UK) or a modified Robert Jones bandage immediately after surgery. The cold compression dressing was used for a minimum of 6 h per day throughout the hospital stay, and the modified Robert Jones bandage remained in place for 48 h from the time of operation. The 2 groups of patients were compared during their hospital stay for blood loss, range of movement, pain scores and need for analgesia. No difference was found between the 2 groups except for less blood loss in the surgical drains in the cold compression group (P < 0.05). Postoperative complications were seen in both groups, but no complication was associated with either the cold compression dressing or the modified Robert Jones bandage.

Periprosthetic bone mineral density changes with femoral components of differing design philosophy.

We measured the bone mineral density in 22 patients with the cylindrical stemmed cobalt-chrome AML prosthesis (collared) and in 22 patients with the tapered stem titanium CLS prosthesis (collarless). DEXA scanning was undertaken at a mean of 40 months in the AML and 52 months in the CLS group from the time of implant insertion. In both groups the greatest mean loss of BMD was found in Gruen zone 7 and the least change in Gruen zone 5. In all zones the BMD loss was greater in the AML group but only statistically significant in zones 6 (P<0.05) and 7 (P<0.01). Although numerous factors affect BMD changes around cementless implants, this study suggests that less bone loss can be associated with the titanium CLS stem.

Photographic wound documentation after open fracture.

More than 3000 open fractures occur in UK each year. They require early assessment and meticulous treatment in order to avoid devastating complications. The British Orthopaedic Association and British Association of Plastic Surgeons Working Party recommend that an instant photograph be taken of an open wound prior to the application of a dressing. The dressing can then remain undisturbed until the definitive surgical debridement is performed in theatre. Such practice reduces nosocomial infection. Fifty-one accident and emergency departments were surveyed by the means of a telephone questionnaire. Forty-one percent were unable to photograph an open fracture wound. A further 20% had no access to a camera outside of office hours. The cheap, simple and effective recommendations of the Working party are not being followed.

Femoral metastatic fractures treated with intramedullary nailing.

Between 1993 and 1998, 49 consecutive patients with impending or complete pathological fractures of the femur due to metastatic bone disease were treated with intramedullary nailing. Twenty-four were treated with a long Gamma nail and 32 with an AO nail with a cephalomedullary spiral blade. Both implants gave a good functional result with relief of pain and improved mobility with no difference in morbidity between either group (P>0.05).

Trapeziectomy for basal thumb joint osteoarthritis: 3- to 19-year follow-up.

A consecutive series of 40 trapeziectomies in 30 patients with basal thumb joint osteoarthritis was reviewed. Sixteen thumbs had pan-trapezial and 24 thumbs trapeziometacarpal osteoarthritis. Simple excision without soft tissue interposition was performed by the same surgeon using an identical surgical technique. Twenty-eight patients were female (mean age 57 years) with a mean follow-up of 11 (3-19) years. Twenty-eight patients were satisfied with their operation, with 26 thumbs being pain free. Thumb pinch strength was improved by 40% compared to preoperative values, but still remained 22% weaker than the non-operated side.

Xanthogranulomatous pyelonephritis--a rare case of fistula between colon and kidney.

We report the case of a 63 year old lady with xanthogranulomatous pyelonephritis. The treatment of choice is nephrectomy. At operation a fistula between large bowel and kidney was found requiring bowel resection. This is a rare complication of xanthogranulomatous pyelonephritis.

Spinal cord monitoring in operations for neuromuscular scoliosis.

We reviewed retrospectively the role of monitoring of somatosensory spinal evoked potentials (SSEP) in 99 patients with neuromuscular scoliosis who had had operative correction with Luque-Galveston rods and sublaminar wiring. Our findings showed that SSEP monitoring was useful and that a 50% decrease in the amplitude of the trace optimised both sensitivity and specificity. The detection of true-positive results was higher than in cases of idiopathic scoliosis, but the method was less sensitive and specific and there were more false-negative results. In contrast with the findings in idiopathic scoliosis, recovery of the trace was associated with a 50% to 60% risk of neurological impairment. Only one permanent injury occurred during the use of this technique, and any temporary impairment resolved within two months.

Acute compartment syndrome of the thigh after weight training.

Compartment syndrome of the thigh is a rare but serious condition that is normally associated with closed trauma or compressive injury. A case of acute compartment syndrome of the thigh occurred in a 16 year old boy after intensive weight training. There was no evidence of muscle tear or focal haemorrhage during subsequent fasciotomy.

Dysphagia--a presenting symptom of forestier disease.

We describe the case of a 48-year-old lady who developed dysphagia to solids. Barium swallow and lateral spine radiographs confirmed Forestier disease.

Paraganglionic phaeochromocytoma presenting twelve years after adrenalectomy.

We present a case report of recurrent hypertension in a 43-year-old man 12 years after undergoing right adrenalectomy for phaeochromocytoma. Further investigations showed a tumour arising from the right paravertebral chain and raised urinary noradrenaline levels. Histological examination after surgical excision found the tumour to be a paraganglionic phaeochromocytoma.