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S J Mubarak

Publications and source records attributed to S J Mubarak.

At least 19 recordsLinked to original sources

Extensor retinaculum syndrome of the ankle after injury to the distal tibial physis.

We describe six patients aged from 10 to 15 years who, after injury to the distal tibial physis, presented with the following clinical findings: 1) severe pain and swelling of the ankle; 2) hypoaesthesia or anaesthesia in the web space of the great toe; 3) weakness of extensor hallucis longus and extensor digitorum communis; and 4) pain on passive flexion of the toes, especially the great toe. In four patients, the fractures were not reduced for more than 24 hours. The intramuscular pressure beneath the superior extensor retinaculum of the ankle was greater than 40 mmHg in all cases (40 to 130 mmHg), and less than 20 mmHg in the anterior compartment. Treatment consisted of release of the superior extensor retinaculum and stabilisation of the fracture. All patients had prompt relief of pain and improved strength and sensation within 24 hours, although two had some residual numbness in the web space of the great toe.

Adolescent↗

Altered fibular growth patterns after tibiofibular synostosis in children.

BACKGROUND: Iatrogenic synostosis of the tibia and fibula following an operation on the leg in a child has been reported rarely in the literature, and the effects of this complication on future growth, alignment, and function are not known. This is a retrospective case series, from one institution, of crossunions of the distal parts of the tibia and fibula complicating operations on the leg in children. The purpose is to alert surgeons to this possible complication. METHODS: The senior author identified eight cases of iatrogenic tibiofibular synostosis seen in children since 1985. The patients had various diagnoses and were from the practices of four pediatric orthopaedic surgeons. Synostosis developed in six patients after osteotomies of the distal parts of the tibia and fibula, in one after internal fixation of distal tibial and fibular metaphyseal fractures through a single incision, and in one after posterior transfer of the anterior tibialis tendon through the interosseous membrane combined with peroneus brevis transfer to the calcaneus. Medical records were reviewed, and preoperative and follow-up radiographs were analyzed for changes in the relative positions of the proximal and distal tibial and fibular physes and in the alignment of the ankle. RESULTS: Five patients were symptomatic after crossunion; they presented with prominence of the proximal part of the fibula, ankle deformity, or ankle pain. Three patients were asymptomatic, and a synostosis was identified on routine follow-up radiographs. Intraoperative technical errors caused two of the crossunions; the cause of the others was unknown. Following tibiofibular synostosis, growth disturbances were noted radiographically in every patient. The normal growth pattern of distal migration of the fibula relative to the tibia was reversed, resulting in a decreased distance between the proximal physes of the tibia and fibula as well as proximal migration of the distal fibular physis relative to the distal part of the tibia. Shortening of the lateral malleolus led to greater valgus alignment of the ankle. CONCLUSIONS: Tibiofibular synostosis can complicate an operation on the leg in a child. After crossunion, the normal distal movement of the fibula relative to the tibia is disrupted, resulting in shortening of the lateral malleolus and ankle valgus as well as prominence of the fibular head at the knee. The synostosis also interferes with the normal motion that occurs between the tibia and fibula with weight-bearing, potentially leading to ankle pain.

Ankle Joint↗

Double-blind study of botulinum A toxin injections into the gastrocnemius muscle in patients with cerebral palsy.

The purpose of this study was to quantify the gait of subjects receiving two injections of either botulinum A toxin or saline vehicle into the gastrocnemius muscle(s). The study group consisted of cerebral palsy patients who walked with an equinus gait pattern. This study was a randomized, double-blinded, parallel clinical trial of 20 subjects. All were studied by gait analysis before and after the injections. There were no adverse effects. Peak ankle dorsiflexion in stance and swing significantly improved in subjects who received the drug and not in controls. Results of this double blind study give support to the short term efficacy of botulinum toxin A to improve gait in selected patients with cerebral palsy.

Ankle Joint↗

Current concepts in the pathophysiology, evaluation, and diagnosis of compartment syndrome.

This article reviews present knowledge of the pathophysiology and diagnosis of acute compartment syndromes. Recent results using compression of legs in normal volunteers provide objective data concerning local pressure thresholds for neuromuscular dysfunction in the anterior compartment. Results with this model indicate that a progression of neuromuscular deficits occurs when IMP increases to within 35 to 40 mm Hg of diastolic blood pressure. These findings provide useful information on the diagnosis and compression thresholds for acute compartment syndromes. Time factors are also important, however, and usually are incompletely known in most cases of acute compartment syndrome. Although the slit catheter is a very good technique for monitoring IMP during rest, these catheters and their associated extracorporeal transducer systems are not ideal. Recently developed miniature transducer-tipped catheters and, perhaps, future development of noninvasive techniques may provide accurate recordings of IMP in patients with acute compartment syndromes.

Acute Disease↗

Anterior release and fusion in pediatric spinal deformity. A comparison of early outcome and cost of thoracoscopic and open thoracotomy approaches.

STUDY DESIGN: A consecutive series of patients undergoing thoracoscopic anterior spinal release and fusion for scoliosis or kyphosis was compared with a consecutive series of patients treated with an open thoracotomy approach. OBJECTIVES: To compare the early clinical results, costs, and charges of performing an anterior thoracic spinal release and fusion with the two approaches. SUMMARY OF BACKGROUND DATA: The thoracoscopic approach to the spine is gaining acceptance, yet there are little data comparing the technique with standard open methods for the treatment of spinal deformity. METHODS: The first 14 thoracoscopic cases performed at the authors' hospital were compared with 18 open thoracotomy cases treated during the previous 12-month period. In each case the discs were excised and bone grafted before performing a posterior fusion. The early clinical outcomes and the hospital charges/costs were analyzed. RESULTS: The percent curve correction was similar between the thoracoscopic and open methods: scoliosis 56% and 60%, respectively; kyphosis, 88% and 94%, respectively. The blood loss and complication rates were similar between the two groups; however, the chest tube output was greater in the thoracoscopic group. The length of hospital stay was not reduced, and the cost of the open procedure is 29% less than the thoracoscopic approach. The minimally invasive thoracoscopic approach avoids cutting the chest/shoulder musculature, greatly decreasing the morbidity of anterior spinal surgery. CONCLUSIONS: The thoracoscopic technique is a safe and effective alternative to open thoracotomy in the approach to the anterior thoracic spine for the treatment of pediatric and adolescent spinal deformity.

Adolescent↗

Managing complications of posterior spinal instrumentation and fusion.

Complications of posterior spinal instrumentation for adolescent idiopathic scoliosis are often preventable. Preoperative planning helps to minimize intraoperative and postoperative problems. Late recurrence of rotational deformity (crankshaft) in skeletally immature patients can be prevented by adding anterior surgery. Intraoperative complications are minimized by controlled hypotensive anesthesia and sequencing of surgical steps to allow for autocoagulation, reducing blood loss. Use of spinal cord monitoring, Stagnara wakeup test, and careful distraction decreases the risk of neurologic deficit. Good hook-site preparation helps avoid dural tears. The incidence of postoperative pneumothorax and hemothorax is decreased by careful hook attachment, avoiding pleural penetration, judicious use of rib excision thoracoplasty, and roentgenographic verification of central venous pressure line position. Postoperative recommendations include bed position at 30 degrees, frequent log rolling, incentive spirometry, early sitting and standing, early Foley catheter and nasogastric tube removal, prophylactic antibiotics, and prompt attention to wound infections. Postoperative orthotic wear, prescribed exercise, and activity restriction decrease the risk of early instrumentation failure and help correct early postoperative trunk imbalance. The late complications include suspected pseudarthrosis; this should be surgically treated again if there is persistent pain or marked loss of curve correction.

Adolescent↗

One-stage correction of the spastic dislocated hip. Use of pericapsular acetabuloplasty to improve coverage.

We performed a combined one-stage approach for the treatment of eighteen spastic subluxated or dislocated hips in eleven children who had cerebral palsy. All patients were between five and thirteen years old and had spastic subluxation or dislocation of the hip and severe acetabular dysplasia. The operation consisted of release of the adductors, psoas, and proximal hamstrings; a femoral-shortening varusderotation osteotomy; and a pericapsular pelvic osteotomy. The pelvic osteotomy was designed to increase superolateral coverage of the femoral head in the elongated acetabulum, which had erosion of the superior and lateral aspects. At the latest follow-up (mean duration, six years and ten months), seventeen of the eighteen hips remained anatomically reduced.

Acetabulum↗

Acute compartment syndrome. Effect of dermotomy on fascial decompression in the leg.

Prompt surgical decompression is the only means of preventing the late sequelae of ischaemic contracture in post-traumatic compartment syndromes. However, controversy exists regarding the length of dermotomy required for adequate decompression in the lower extremity. This study investigated the skin envelope as a potential contributing factor. Wide fascial releases were performed through limited 8 cm incisions in eight cases of post-traumatic lower extremity compartment syndrome. In nine of 29 compartments the pressure remained greater than 30 mmHg. Lengthening the skin incisions to an average of 16 cm decreased intracompartmental pressures significantly. This study documents the skin envelope as a contributing factor in acute compartment syndromes of the leg. The use of generous skin incisions is supported and the need for intra-operative compartment pressure measurements in the treatment of this condition is emphasised.

Acute Disease↗

Complications of posterior arthrodesis of the cervical spine in patients who have Down syndrome.

Ten patients who had Down syndrome and had had a posterior arthrodesis of the upper cervical spine were studied. The mean age at the time of the operation was 8.9 years, and the patients had been followed for three days to forty-nine months. Complications related to the operation occurred in all patients. They included infection and dehiscence at the site of the wound, incomplete reduction of the atlanto-axial joint, instability of the adjacent motion segment, neurological sequelae, resorption of the autogenous bone graft, and death in the postoperative period. Resorption of the bone graft, which occurred in six of the patients, has not previously been reported in patients who have Down syndrome, to our knowledge. Several theoretical mechanisms for this complication are proposed. We recommend non-operative management for patients who have Down syndrome and atlanto-axial instability without neurological signs or symptoms. If the severity of symptoms necessitates a posterior arthrodesis, a high rate of complications must be anticipated.

Adolescent↗

A new "transducer-tipped" fiber optic catheter for measuring intramuscular pressures.

Laboratory and clinical tests were used to determine the efficacy of a new fiber optic "transducer-tipped" catheter for measuring intramuscular pressures. When pressures ranging from 0 to 250 mm Hg were applied by a mercury manometer, the fiber optic system accurately recorded the pressures. In addition, the fiber optic system showed long-term stability by accurately recording the manometer pressure over a 3 day period. The Slit system showed a higher magnitude of hydrostatic pressure artifacts with catheter tip movement as compared to the fiber optic system. The two catheters showed no difference when measuring pressures in pig muscle at rest or when being compressed throughout a range of 0 to 250 mm Hg. In human volunteers, both catheters measured essentially equal pressures at rest, during venous stasis, and during a combination of venous stasis and compression. For long-term assessment, the Slit system required as many as three saline flushes, whereas the fiber optic system measured pressures continuously without manipulation. We conclude that the fiber optic system is as accurate as the Slit catheter for measuring tissue fluid pressures at rest. In addition, the fiber optic system offers distinct advantages over conventional fluid-filled systems for measuring intramuscular pressures due to a lack of hydrostatic pressure artifacts caused by limb position and to the lack of flushing for long-term measurements.

Adult↗

Kappa Delta Award paper. Tissue fluid pressures: from basic research tools to clinical applications.

The two basic research tools developed to measure tissue fluid pressure (wick catheter) and osmotic pressure (colloid osmometer) have undergone extensive validation and refinement over the past 20 years. Using these techniques, basic science investigations were undertaken of edema in Amazon reptiles, pressure-volume relations in animals and plants, adaptive physiology of Antarctic penguins and fishes, edema in spawning salmon, tissue fluid balance in humans under normal conditions and during simulated weightlessness, and orthostatic adaptation in a mammal with high and variable blood pressures--the giraffe. Following and sometimes paralleling this basic research have been several clinical applications related to use of our colloid osmometer and wick technique. Applications of the osmometer have included insights into (a) reduced osmotic pressure of sickle-cell hemoglobin with deoxygenation and (b) reduced swelling pressure of human nucleus pulposus with hydration or certain enzymes. Clinical uses of the wick technique have included (a) improvement of diagnosis and treatment of acute and chronic compartment syndromes, (b) elucidation of tissue pressure thresholds for neuromuscular dysfunction, and (c) development of a better tourniquet design for orthopaedics. This article demonstrates that basic research tools open up areas of basic, applied, and clinical research.

Animals↗

Compartment syndromes.

The compartment syndrome is defined as a condition in which high pressure within a closed fascial space (muscle compartment) reduces capillary blood perfusion below the level necessary for tissue viability'. This condition occurs in acute and chronic (exertional) forms, and may be secondary to a variety of causes. The end-result of an extended period of elevated intramuscular pressure may be the development of irreversible tissue injury and Volkmann's contracture. The goal of treatment of the compartment syndrome is the reduction of intracompartmental pressure thus facilitating reperfusion of ischaemic tissue and this goal may be achieved by decompressive fasciotomy. Controversy exists regarding the critical pressure-time thresholds for surgical decompression and the optimal diagnostic methods of measuring intracompartmental pressures. This paper will update and review some current knowledge regarding the pathophysiology, aetiology, diagnosis, and treatment of the acute compartment syndrome.

Capillaries↗

Management of chronic exertional anterior compartment syndrome of the lower extremity.

Eighteen patients (28 compartments) with chronic exertional compartment syndrome and 14 normal asymptomatic volunteers (18 compartments) were studied. Evaluation included clinical assessment followed by quantitative determination of intracompartmental pressures as monitored by wick or slit catheters before and after exercise. Intramuscular pressures measuring greater than or equal to 10 mmHg at rest and/or greater than or equal to 25 mmHg five minutes after exercise were defined as abnormally elevated. The patients with chronic compartment syndrome described reproducible exertional anterolateral leg pain, and 39% of these patients had a fascial hernia. Such a defect was present in less than five percent of the normal volunteers. Nonsurgical treatment was selected by five patients and all five reported persistent inability to participate in athletics because of their exertional pain. Of the remaining 13 patients, 12 were treated by decompressive fasciotomy and 11 of the 12 (92%) had pain relief and increased exercise tolerance. A single patient had had fascial closure instead of fasciotomy, and this procedure produced an acute compartment syndrome. Effective treatment of the chronic compartment syndrome consists of reduction of exertional activities or surgical decompression by fasciotomy.

Adolescent↗