Chopart amputation with tibiotalocalcaneal arthrodesis and free flap reconstruction for severe foot crush injury

Aims

This study reports the outcomes of a technique of soft-tissue coverage and Chopart amputation for severe crush injuries of the forefoot.

Patients and Methods

Between January 2012 to December 2016, 12 patients (nine male; three female, mean age 38.58 years; 26 to 55) with severe foot crush injury underwent treatment in our institute. All patients were followed-up for at least one year. Their medical records, imaging, visual analogue scale score, walking ability, complications, and functional outcomes one year postoperatively based on the American Orthopedic Foot and Ankle Society (AOFAS) and 36-Item Short-Form Health Survey (SF-36) scores were reviewed.

Results

The mean length of follow-up was 18.6 months (13 to 28). Two patients had a local infection, flap necrosis was seen in one patient, and one patient experienced a skin graft wound healing delay. Of the 12 patients, one had persistent infection and eventually required below-knee amputation, but pain-free walking was achieved in all the other patients. The mean one-year postoperative AOFAS and SF-36 scores were 75.6 (68 to 80) and 82 (74 to 88), respectively.

Conclusion

Although our sample size was small, we believe that this treatment method may be a valuable alternative for treating severe foot crush injuries. Cite this article: Bone Joint J 2018;100-B:1359–63.

The protective role of nitric oxide-dependent innate immunosuppression in the early stage of cartilage damage in rats: Role of nitric oxide in cartilage damage

Objectives

Osteoarthritis (OA) is the most common form of arthritis, affecting approximately 15% of the human population. Recently, increased concentration of nitric oxide in serum and synovial fluid in patients with OA has been observed. However, the exact role of nitric oxide in the initiation of OA has not been elucidated. The aim of the present study was to investigate the role of nitric oxide in innate immune regulation during OA initiation in rats.

Methods

Rat OA was induced by performing meniscectomy surgery while cartilage samples were collected 0, 7, and 14 days after surgery. Cartilage cytokine levels were determined by using enzyme-linked immunosorbent assay, while other proteins were assessed by using Western blot

Results

In the time course of the study, nitric oxide was increased seven and 14 days after OA induction. Pro-inflammatory cytokines including tumour necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were decreased. L-NG-Nitroarginine methyl ester (L-NAME, a non-specific nitric oxide synthase inhibitor) significantly decreased cartilage nitric oxide and blocked immune suppression. Further, L-NAME decreased Matrix metalloproteinase (MMPs) and increased tissue inhibitor of metalloproteinase (TIMP) expression in meniscectomised rats.

Conclusion

Nitric oxide-dependent innate immune suppression protects cartilage from damage in the early stages of OA initiation in rats.

Cite this article: C-C. Hsu, C-L. Lin, I-M. Jou, P-H. Wang, J-S. Lee. The protective role of nitric oxide-dependent innate immunosuppression in the early stage of cartilage damage in rats: Role of nitric oxide in ca rtilage da mage. Bone Joint Res 2017;6:253–258. DOI: 10.1302/2046-3758.64.BJJ-2016-0161.R1.

Ultrasound-Guided Percutaneous Radiofrequency Lesioning When Treating Recalcitrant Plantar Fasciitis: Clinical Results

PURPOSE

We evaluated the effects of ultrasound (US)-guided percutaneous radiofrequency thermal lesioning (RTL) and the impact of obesity when treating patients with recalcitrant plantar fasciitis.

MATERIALS AND METHODS

30 consecutive patients were enrolled. The visual analog scale (VAS), American Orthopedic Foot-Ankle Society (AOFAS) Ankle-Hindfoot Score, and plantar fascia thickness measured using US were recorded at baseline and at follow-up 1, 3, 6, and 12 months after surgery under local anesthesia.

RESULTS

12 patients in the obese (BMI ≥ 30 kg/m(2)) group and 18 patients in the non-obese group. There were significant postoperative decreases in VAS scores and in fascial thickness, and an increase in the AOFAS scores (all p < 0.001). The obese group showed delayed pain and functional improvement within the first 3 months after the index procedure (p < 0.01). Significant pain reduction and functional improvement were apparent earlier (after 1 month, p < 0.001) in the non-obese group than in the obese group (after 3 months, p < 0.05). Fascia thickness was positively correlated with the VAS score and negatively correlated with the AOFAS score (both p < 0.001).

CONCLUSION

US should be regarded as a useful objective tool to guide RTL and to monitor the effectiveness of treatment. US-guided percutaneous RTL for recalcitrant PF is a minimally invasive treatment option that yields satisfactory results. Therefore, it should at least be considered before using more invasive procedures. Moreover, obesity leads to delayed improvement but does not affect overall outcome after 12 months. Plantar fascial thickness was correlated with VAS and AOFAS scores.

T helper cells promote disease progression of osteoarthritis by inducing macrophage inflammatory protein-1γ

OBJECTIVE

Immune cells are involved in the pathogenesis of osteoarthritis (OA). We examined the effects of T helper (Th) cells, which induce the expression of macrophage inflammatory protein (MIP-1γ), on the progression of OA.

DESIGN

Using anterior cruciate ligament-transection (ACLT), we induced OA in one hind-leg knee joint of B6 mice. The CD4(+) T cells from splenocytes and synovium were flow-cytometrically and immunochemically evaluated, respectively. The knee joints were histologically assessed for manifestations of OA. MIP-1γ levels and nuclear factor-κB (NF-κB) in the knee joints were measured using enzyme-linked immunosorbent and immunoblotting assays, respectively; osteoclastogenesis was detected by tartrate-resistant acid phosphatase (TRAP) staining. The inflammatory responses and MIP-1γ expression were examined using immunohistochemistry.

RESULTS

The number of CD4(+) T cells and the expression of interferon-γ (IFN-γ) increased during OA onset (30 days after ACLT) and then decreased at a later stage of OA (90 days after ACLT). Tissue damage induced by CD4(+) T cells was evident at the later stage. The activation of CD4(+) T cells induced the expression of MIP-1γ and NF-κB. The expression of MIP-1γ can be detected in synovium which CD4(+) T cells were infiltrated. The increased MIP-1γ expression caused an increase in the number of osteoclasts in joints. The regulation of CD4(+) T cells was accompanied by increased macrophage infiltration and matrix metalloproteinase (MMP)-9 expression. Histopathological examinations revealed that CD4(+) T cell knockout (CD4(-/-)) mice had less expression of MIP-1γ and slower cartilage degeneration than control mice had.

CONCLUSIONS

CD4(+) T cells were activated during the onset of OA, but cartilage damage was more prominent at a later stage. CD4(+) T cells were involved in the pathogenesis of OA: they induced MIP-1γ expression and subsequent osteoclast formation.

Effects of topical corticosteroids on the sciatic nerve: an experimental study to adduce the safety in treating carpal tunnel syndrome

Despite known detrimental effects on the blood flow and histology of nerves after intraneural corticosteroid injection, the neurotoxic effect of corticosteroids remains unclear. We investigated the effect of topical dexamethasone on nerve function. Two sponge strips soaked with dexamethasone at doses of 0.8, 1.6, and 3.2 mg were placed under and over the left sciatic nerve of adult Wistar rats for 30 minutes. Mixed-nerve-elicited somatosensory evoked potentials and dermatomal somatosensory evoked potentials were evaluated immediately and repeated together with functional tests and histology 2 weeks later. Evoked potential amplitude was dose-dependently lower and latency was prolonged in dexamethasone-treated sciatic nerves compared to controls. The suppression persisted with incomplete recovery for at least 4 hours, but differences between treated and control nerves were not significant after 2 weeks. Topical dexamethasone adversely affected neural conduction in a dose-dependent manner. Our results suggest that caution is required when using large doses of corticosteroid for injection of the carpal tunnel.

Model-based segmentation of flexor tendons from magnetic resonance images of finger joints

Trigger finger is a common hand disease, causing swelling, painful popping and clicking in moving the affected finger joint. To better evaluate patients with trigger finger, segmentation of flexor tendons from magnetic resonance (MR) images of finger joints, which can offer detailed structural information of tendons to clinicians, is essential. This paper presents a novel model-based method with three stages for automatically segmenting the flexor tendons. In the first stage, a set of tendon contour models (TCMs) is initialized from the most proximal cross-sectional image via two-step ellipse estimation. Each of the TCMs is then propagated to its distally adjacent image by affine registration. The propagation is sequentially performed along the proximal-distal direction until the most distal image is reached, as the second stage of segmentation. The TCMs on each cross-sectional image are refined in the last stage with the snake deformation. MR volumes of three subjects were used to validate the segmentation accuracy. Compared with the manual results, our method showed good accuracy with small average margins of errors (within 0.5 mm) and large overlapping ratio (dice similarity coefficient above 0.8). Overall, the proposed method has great potential for morphological change assessment of flexor tendons and pulley-tendon system modeling for image guided surgery.

An ultrasonographic and anatomical study of carpal tunnel, with special emphasis on the safe zones in percutaneous release

We examined 40 wrists of 12 embalmed and eight fresh cadavers and defined the relative position of the flexor retinaculum to the neurovascular structure, ultrasonographic markers and safe zones by ultrasonography and anatomical dissection. Both longitudinal and transverse ultrasonographic sections clearly depicted the flexor retinaculum, neurovascular bundles, median nerve, flexor tendons and bony boundaries of the underlying joints. Topographic measurement showed [i] good correlation between the actual extent of the flexor retinaculum and the ultrasonographically determined distance between bony landmarks in all hands, and [ii] the widths and lengths of well-defined safe zones. A comparison study confirmed the accuracy of ultrasonography. We conclude that these ultrasonographic landmarks can locate the flexor retinaculum and facilitate safe and complete carpal tunnel release with open or minimally invasive techniques.

Sonographically assisted percutaneous release of the a1 pulley: a new surgical technique for treating trigger digit

This study introduces a sonographically assisted percutaneous technique for releasing trigger digits which provides direct visualization of the release and avoids the risks of incomplete release and injury to adjacent neurovascular structures associated with other percutaneous release techniques. The "safe zone" and an estimate of the size of the A1 pulley were determined in a separate cadaver study. We then used these landmarks in a prospective clinical study of 107 digits in 83 consecutive patients treated by this technique. During the follow-ups of between 9 and 15 months, we evaluated 104 digits in 80 patients. Pain was absent in 101 digits (97%) and considerably improved in the other three (3%). All mechanical problems had been resolved and none recurred during follow-up. This technique allows the surgeon to see and monitor, precisely, the percutaneous division of the A1 pulley without open surgery and, therefore, to avoid the inherent risks of percutaneous and open surgical release.

Gait analysis after total hip arthroplasty with leg-length equalization in women with unilateral congenital complete dislocation of the hip--comparison with untreated patients

Patients with Crowe Type-IV congenital dislocation of the hip (CDH) show significant clinical improvement after total hip arthroplasty (THA) because this surgery greatly reduces pain. Concomitant leg-length equalization in unilateral patients--a controversial procedure--theoretically should significantly improve these patients' ability to walk efficiently and comfortably. To understand the impact of leg-length equalization on these patients, we compared their gait parameters with those of untreated patients without pain but with leg-length discrepancy. Using a motion analysis system, three force platforms and computer calculation, the gait parameters during level walking of 22 women with unilateral Crowe Type-IV CDH were studied at an average of 58 months (27-98 months) following a successful cementless THA. The socket was placed in the best bone stock, which was close to the level of the true acetabulum. The leg-length discrepancy was equalized to within 2 cm in all patients. The Harris hip score averaged 94.8 (range, 88-100) at the time of the study. Nine women with untreated unilateral Crowe Type-IV CDH without major pain but with an average leg-length discrepancy of 4.7 cm (range, 2.5-6 cm) were also studied for comparison. The treated subjects (Group 1; THA and leg-length equalization) walked faster and had gait parameters with better bilateral symmetry than the untreated subjects (Group 2). We concluded that leg-length equalization in addition to THA in patients with unilateral Crowe Type-IV CDH significantly improves gait symmetry and efficiency.

Direct Tramadol Application on Sciatic Nerve Inhibits Spinal Somatosensory Evoked Potentials in Rats

We sought to determine the possible neural conduction blockade of tramadol and whether there is evidence of localized neural toxicity with spinal somatosensory evoked potential (SSEP) measurements. Male Wistar rats were used. SSEP, elicited by supramaximally stimulating the hind paw and recorded from the thoracolumbar and the first and second lumbar interspinous ligaments, was monitored. SSEPs were obtained before drug application as the pretreatment baseline and measured every 15 min after treatment for 2 h and at 60-min intervals thereafter until SSEP returned to baseline or for another 4 h. Two small strips of Gelfoam (0.6 x 1.0 cm(2)) soaked with the drug were placed under and over the left sciatic nerve for a 30-min period. Gelfoam was prepared with tramadol hydrochloride (Tramal; the US trade name is Ultram) 5, 2.5, and 1.25 mg, diluted if needed with saline to a total volume of 100 microL (5%, 2.5%, and 1.25%, respectively). The control data were obtained from the right side limb with normal saline by following the same method. Spinal SSEPs were measured after 48 h to detect the late neural damage. The results showed that direct tramadol application on sciatic nerves dose-dependently reduced both the amplitude and conduction velocity of SSEPs when compared with the pretreatment baseline. All SSEPs returned to pretreatment baseline, and no significant changes of SSEP between bilateral limbs were noted at the 48-h measurements. No evidence of irreversible conduction blockade indicative of local neural toxicity was seen. Pretreatment with naloxone 1 mg/kg failed to block the changes of SSEP produced by 2.5% tramadol 100 microL. We conclude that tramadol exerts a local anesthetic-type effect on peripheral nerves.

Synchronous pyomyositis and septic hip arthritis

The authors report a rare concomitant pyogenic infection of the iliopsoas, iliacus and external obturator muscles and of the hip joint in a 68-year-old woman. Because the patient showed the classic symptomatic triad of limping, hip pain and fever, in addition to positive hip arthrocentesis, the diagnosis of septic hip arthritis was routine, but the simultaneous pyomyositis was almost overlooked. Unusual localised heat and swelling on the front of the proximal thigh prompted a CT scan that identified remarkable muscle abscesses in addition to the septic arthritis. Surgical debridement and antibiotics resolved the infection relatively rapidly without sequelae. We noted that reaching a definitive diagnosis of such a concomitant infection requires a suspicion of the presence of pyomyositis, which can be definitively determined using advanced imaging studies.

Brachial plexus injury following coronary artery bypass surgery: a case report

Postoperative brachial plexus injury, often manifesting as a variety of upper extremity neuropathies, is a recognized and not uncommon complication following cardiac surgery that requires a median sternotomy. In general, the vast majority of its neurological symptoms are transient and need no treatment. Nevertheless, in very rare cases, the peripheral neuropathies will persist and cause disability. We treated a 67-year-old male patient complicated by permanent paresthesia and paralysis of the left upper extremity after an eventful coronary artery bypass surgery. The nerve conduction measurements and electromyography all revealed a C5 to T1 lesion. After carefully reviewing the surgical course and referring to the published literature, we tentatively concluded that compression or overstretching produced by wide and prolonged sternal separation of the brachial plexus was the most likely etiology. Asymmetrical traction of the sternal halves during internal mammary artery harvesting might also have contributed to this nerve injury. We surmised, therefore, that brachial plexus injury could be minimized by an exact median sternotomy, a lower position and the smallest possible opening for the sternal retractor, and the avoidance of constant and asymmetrical traction on the sternal halves.

Simplified rat intubation using a new oropharyngeal intubation wedge

Our new oropharyngeal intubation wedge made from a plastic 3-ml syringe has been used successfully for the expansion of the oropharyngeal cavity and visualization of vocal cords for endotracheal intubation in the rat. All the animals we used tolerated the intubation and ventilation procedures in a series of experiments. After the proper setting of the respirator, vital signs were maintained within normal range. The postmortem examination and measurements in the upper airway confirmed that the endotracheal tube was properly sited and also demonstrated the precise size of the device that should be used. The main advantages of this method include low cost, simplicity, and reliability. Furthermore, because no expensive, elaborate, difficult-to-operate, or hard-to-get special equipment is needed, this technique can be used in every laboratory.

Effects of core body temperature on changes in spinal somatosensory-evoked potential in acute spinal cord compression injury: an experimental study in the rat

STUDY DESIGN

Acute spinal cord injury was induced by a clip compression model in rats to approximate spinal cord injury encountered in spinal surgery. Spinal somatosensory-evoked potential neuromonitoring was used to study the electrophysiologic change.

OBJECTIVES

To compare and correlate changes in evoked potential after acute compression at different core temperatures with postoperative neurologic function and histologic change, to evaluate current intraoperative neuromonitoring warning criteria for neural damage, and to confirm the protective effect of hypothermia in acute spinal cord compression injury by electrophysiologic, histologic, and clinical observation.

SUMMARY OF BACKGROUND DATA

With the increase in aggressive correction of spinal deformities, and the invasiveness of surgical instruments, the incidence of neurologic complication appears to have increased despite the availability of sensitive intraoperative neuromonitoring techniques designed to alert surgeons to impending neural damage. Many reasons have been given for the frequent failures of neuromonitoring, but the influence of temperature-a very important and frequently encountered factor-on evoked potential has not been well documented. Specifically, decrease in amplitude and elongation of latency seem not to have been sufficiently taken into account when intraoperative neuromonitoring levels were interpreted and when acceptable intraoperative warning criteria were determined.

METHODS

Experimental acute spinal cord injury was induced in rats by clip compression for two different intervals and at three different core temperatures. Spinal somatosensory-evoked potential, elicited by stimulating the median nerve and recorded from the cervical interspinous C2-C3, was monitored immediately before and after compression, and at 15-minute intervals for 1 hour.

RESULTS

Spinal somatosensory-evoked potential change is almost parallel to temperature-based amplitude reduction and latency elongation. Significant neurologic damage induced by acute compression of the cervical spinal cord produced a degree of effect on the amplitude of spinal somatosensory-evoked potential in normothermic conditions that differed from the effect in moderately hypothermic conditions. Using the same electromonitoring criteria,moderately hypothermic groups showed a significantly higher false-negative rate statistically (35%) than normothermic groups (10%).

CONCLUSIONS

Systemic cooling may protect against the detrimental effects of aggressive spinal surgical procedures. There is still not enough published information available to establish statistically and ethically acceptable intraoperative neuromonitoring warning and intervention criteria conclusively. Therefore, an urgent need exists for further investigation. Although a reduction of more than 50% in evoked potential still seems acceptable as an indicator of impending neural function loss, maintenance of more than 50% of baseline evoked potential is no guarantee of normal postoperative neural function, especially at lower than normal temperatures.

Symptomatic and asymptomatic accessory navicular bones: findings of Tc-99m MDP bone scintigraphy

AIM

The accuracy of bone scintigraphy in diagnosing symptomatic accessory navicular bones has not been well studied. We conducted a retrospective study to explore the results and use of scintigraphy in symptomatic and asymptomatic accessory navicular bones.

MATERIALS AND METHODS

Thirteen patients with a total of 13 symptomatic and 10 asymptomatic accessory navicular bones were included in the study. We used a scoring system to grade the scintigraphic abnormalities. The patients' symptoms and scintigraphic findings were recorded.

RESULTS

Though focally increased radiopharmaceutical uptake was observed in all symptomatic accessory naviculars, half of the asymptomatic accessory navicular bones had the same manifestations. The scoring system was of no value in differentiating symptomatic from asymptomatic accessory navicular bones.

CONCLUSION

Bone scintigraphy is a sensitive but not a specific tool for diagnosing a symptomatic accessory navicular.

Changes in conduction, blood flow, histology, and neurological status following acute nerve-stretch injury induced by femoral lengthening

The effects of an acute stretch on evoked potential, blood flow, histological change, and clinical neurological state were studied in a rat model of acute nerve stretch induced by femoral lengthening. The purposes of this study were to assess, in a model of acute limb lengthening, the safe limits of nerve stretch for nerve function, the pathogenesis of nerve dysfunction, the sensitivity of spinal somatosensory evoked potential, and one of the proposed criteria for irreversible compromise of the sciatic nerve. Thirty-two rats were assigned to one of four groups defined by the degree of acute femoral lengthening (8, 16, 24, and 32%). Spinal somatosensory evoked potential at L5/6 following stimulation of the sciatic nerve was recorded before, immediately after, and 30 minutes after lengthening. Sciatic nerve blood flow was measured by laser Doppler flowmetry at the stretched site before and after lengthening. One week after the operation and without further lengthening, clinical neurological status was evaluated by the functional index of the sciatic nerve and histological examination was performed. At the measurement immediately after the procedure, amplitude changed significantly in all groups except for the group with 8% lengthening. In all groups, sciatic nerve blood flow also dropped significantly compared with values for the control side. Moreover, a greater percentage increase in acute lengthening corresponded with more marked changes in spinal somatosensory evoked potential and sciatic nerve blood flow. The groups that underwent acute lengthening of 24 and 32% had significant neurological deficits and histological changes and demonstrated a significant and profound (50%) drop in amplitude and blood flow. We concluded that spinal somatosensory evoked potential is very sensitive and may serve as an effective tool for the early detection of impending acute nerve-stretch injury and that a 50% reduction in amplitude indicates irreversible damage.

The influence of delay and the effect of fibrin sealant on the cut surface of the peripheral nerve. An experimental study in the rat

Thirty-two sciatic nerves in 16 rats were divided to investigate the effect of delay in fixation and the use of fibrin sealant at the site of the division on the nerve end. Specimens were assessed by morphological and morphometric criteria using scanning electron microscopy and longitudinal sections. All specimens showed a protruded nerve end. Wrapping the nerve with fibrin sealant before division and immediate fixation of the specimen resulted in less protrusion.

Pyomyositis--with special reference to the comparison between extra- and intrapelvic muscle abscess

Fifteen patients, nine males and six females, diagnosed with pyomyositis from 1988 to 1994, and followed for an average of 69.8 months, were reviewed. Excluding two children, the average age was 56.6 years. Eleven adults (73.3%) had underlying diseases. The lesions were multiple in five patients (33.3%) and a total of twenty-four muscle abscesses, including eleven extrapelvic and thirteen intrapelvic, were identified. When comparing extra- and intrapelvic pyomyositis, intrapelvic pyomyositis presents a diagnostic challenge requiring a high index of suspicion. Distinct clinical features such as local heat and painful swelling were all identified in extrapelvic pyomyositis, but they rarely (in only two of the thirteen lesions) emerged in intrapelvic pyomyositis. The average time from presentation to diagnosis was significantly longer in intrapelvic than in extrapelvic pyomyositis (1.4 vs 9.7 days). Although aspiration showed a high diagnostic rate in extrapelvic muscle abscesses, it was difficult to perform and was occasionally misinterpreted in intrapelvic cases. Routine X-rays were not helpful in making the diagnosis. CT scan was valuable because it provided positive diagnostic findings in all twelve patients who received one. The causative organisms in our patients were Staphylococcus aureus in eight (53.3%), Escherichia coli in three (20%), and Klebsiella in three (20%). Treatments consisted of parenteral antibiotics for all patients, image-guided aspiration in four patients, and surgical drainage in eleven patients. Two intrapelvic pyomyositis patients expired due to sepsis. At the completion of the study, twelve patients were asymptomatic without sequel, and one patient had a recurrence.

Neuromonitoring of an experimental model of clip compression on the spinal nerve root to characterize acute nerve root injury

OBJECTIVES

To evaluate the sensitivity of an electro-monitoring method in acute nerve root injury, and to determine a proposed criterion for irreversible electrophysiologic degradation.

STUDY DESIGN

Acute nerve root injury was induced by a clip compression model in rabbits, mimicking nerve root injury by a transpedicular screw. A common neuromonitoring technique, spinal somatosensory-evoked potential, was used to study the electrophysiologic change during the procedure.

SUMMARY OF BACKGROUND DATA

With the advent of the transpedicular screw system, increased risk of injury to the spinal root because of the passage of screws is not unexpected. Although both an experimental model and a clinical application in intraoperative neuromonitoring of spinal cord function have been established, the value of neuromonitoring of an acute spinal root injury remains obscure. Several neurophysiologic surveillance techniques have been used successfully to monitor the potential injury to the spinal cord during orthopedic procedures around the spinal cord and spinal column. Spinal somatosensory-evoked potential, which has the advantages of high amplitude and quick recording time, is used to detect nerve root impairment during the insertion of transpedicular screws.

METHODS

Experimental acute nerve root injury was induced in rabbits by direct hemostatic clip compression on the nerve root (S1) during different time intervals. Spinal somatosensory-evoked potential elicited by stimulating the sciatic nerve and recorded from a needle electrode at the L6-L7 interspinous ligament was monitored immediately before and after compression.

RESULTS

Spinal somatosensory-evoked potential is sensitive enough to detect the compromise of a single nerve root and that a decrease in the amplitude is the most reliable and sensitive sign. With this model, there was a statistically significant correlation between the compression time and reduction of amplitude and delay of latency. The criterion for irreversible electrophysiologic change was an amplitude loss of more than 20% and a delay in latency immediately after nerve root compression.

CONCLUSIONS

It was concluded that spinal somatosensory-evoked potential can provide immediate feedback of nerve root injury and should be considered for use during the dynamic phase of transpedicular screw insertion.

Acute median nerve injury due to migration of a Kirschner wire

Migration of orthopaedic implants such as K-wires is not unusual, but migration due to an improperly constructed brace has not been reported. This report describes such a mechanism in a case complicated by acute median nerve injury.

The value of 67Ga-citrate scanning in psoas abscess

Psoas abscess is a serious health problem which presents with non-specific symptoms and signs. To reduce morbidity and mortality, it is important to diagnose the presence and extent of a psoas abscess accurately using imaging studies. Because the 67Ga scan may facilitate the early diagnosis of insidious infection and assist CT-guided percutaneous drainage of the abscess, we examined the value of 67Ga scans in 18 patients with psoas abscess. The imaging results of 67Ga scans (18 patients), computed tomography (CT) (16 patients) and bone scans (13 patients) were analyzed. In this series, concomitant infections were very common (94%) in patients with psoas abscess. For detecting psoas abscess, the sensitivity of 67Ga scanning (92%) and CT (91%) was similar. However, 67Ga scanning is superior to CT in demonstrating concomitant infectious foci at other sites. Bone scanning is a sensitive tool for depicting osteomyelitis, which was common in this series of patients. We also found that increased vascularity in the psoas area was demonstrated by three-phase bone scanning in 60% of patients.

Two-stage cementless revision THR after infection. 5 recurrences in 40 cases followed 2.5-7 years

We revised 40 infected hip prostheses in 40 patients as a two-stage procedure, including intravenous and oral antibiotics, gentamicin beads, and delayed cementless implantation of porous-coated THR. The duration of antibiotic treatment was 8 weeks. The interval from resection to reimplantation was, on average, 48 (8-108) weeks. 39 patients were followed, on average, 4 (2.5-7) years. 5 patients had a recurrent infection. In patients who did not have a recurrent infection, the Harris hip score exceeded 80 in 32 patients. Radiographically, femoral component migration of 2-6 mm was noted in 3 cases. The recurrent infection rate, and the functional and radiographic results are comparable with those obtained using a two-stage procedure with antibiotic cement.

Widespread cutaneous necrosis associated with antiphospholipid syndrome

Widespread cutaneous necrosis as the catastrophic manifestation in antiphospholipid syndrome (APLS) is rather uncommon. Even in the few documented cases, the extensive skin necrosis lesions have been stabilized and regressed with eventual healing utilizing pulse steroid therapy alone or in conjunction with further treatment with plasmapheresis. We describe one case of APLS associated with lupus-like disease. The young female suffered from widespread cutaneous necrosis of the lower legs and gangrene change in the digital end of hands and feet. This condition necessitated amputation of major lower extremities and digital amputation of both hands.

Cementless reimplantation of hydroxyapatite-coated total hips after periprosthetic infections

From February 1991 to July 1993, 26 hydroxyapatite (HA) coated total hips were implanted in 26 patients with infected hip prostheses. Seven were done as one-stage exchange arthroplasties and the other 19 were delayed reimplantations. Successful reimplantation was defined as a functioning hip without recurrence of infection at least 2 years after reimplantation. During a follow-up period of 25 to 54 months, 24 of the reimplantations were successful. Our success rate using the HA-coated prosthesis is similar to previous reports that used antibiotic impregnated bone cement. The HA method avoids the complications encountered with bone cement.

Lumbar lordosis: normal adults

Lumbar curvatures in 149 normal adults from the general population were studied. There were 76 men and 73 women with an average age of 50 years. The mean values of lumbar lordotic angle (LLA), lumbosacral angle (LSA) and sacral inclination angle (SIA) were 33.2 +/- 12.1 degrees, 11.4 +/- 4.7 degrees and 26.4 +/- 10 degrees, respectively. A high correlation was noted between LLA and SIA (r = 0.883, p = 0.0001). LLA is an ideal parameter for the evaluation of lumbar lordosis. The normal value of LLA can be defined as 20-45 degrees with a range of 1 SD. No significant differences were noted in these three angles between males and females in any age group (LLA, p = 0.647; LSA, p = 0.80; SLA, p = 0.189). Also, X-ray findings indicated there were no significant differences between these three angles in spondylotic spines and those spines with a normal appearance from X-ray finding. The average LLA increased with age. Significant lumbar lordotic angle differences were noted between those patients less than 35 years of age and those greater than 60 years, as well as in the 35-60 age group and the greater than 60 age group (p = 0.0056).