Respiratory chain activity in myopathies

Aim: The present study was conducted to find out whether disturbances of respiratory chain enzymes were involved in the pathogenesis of three types of myopathy: Duchenne muscle dystrophy [DMD], limb girdle muscular dystrophy, and steroid-induced myopathies; to assess the extent and nature of these deficits among the three myopathic groups, and to investigate the relation between the severity of muscular disorders- assessed by creatine phosphokinase [CPK] level- and the extent of respiratory chain impairment. Subjects and Fourty myopathic patients as group I [GI]; 10 DMD [GIA], 16 limb girdle dystrophy [GIB], and 14 steroid-induced myopathy [GIC]; and 20 healthy controls as group II [GII] that matches the general features of GI. Cases and controls were subjected to history taking as well as physical examination. Diagnosis of myopathy was established using routine motor and sensory conduction study and concentric needle EMG. Cases and controls were subjected to estimation of respiratory chain complexes; RCI, RCII, RCIII, and RCIV, in neutrophil mitochondria. Results were analysed using t-test between GI and II and F test in between GIA, GIB and GIC. The results revealed a significant decrease of all respiratory chain complexes; RCI, RCII, RCIII, and RCIV; in GI as compared to controls [2878.04 +/- 1085.96 versus 5867.93 +/- 1000.03 micro mol/min/mg protein for RCII, 549.7 +/- 21574 versus 80382+/=119.41 micro mol/min/mg of protein for RCIV, 60654 +/- 162.35 versus 95949 +/- 136.14 micro mol/min/mg of protein for RCIII, and 58.73 +/- 18.08 versus 97.88 +/- 19.06 micro mol/min/mg protein for RCIV. On comparing the 3 subgroups; IA, IB, and IC; the following was found [1] A significant decrease of GIC when compared to GIA and when compared to GIB and when compared to GIB as regards RCI [3234.526 +/- 716.363, 3385.13 +/- 218.603, and 2043.894 +/- 631.967 micro mol/min/mg protein for GIA. GIB, and GIC, respectively, F - 4.331, and P = 0.03]; [2] A significant decrease of GIA when compared to GIB and when compared to GIC as regards RCIV [42.584 +/- 22,9177, 66.947 +/- 10.861, and 60.88 +/- 1532 micro mol/min/mg protein for GIA, GIB, and GIC, respectively, F = 3.67 and P = 0.47]. [3] Nonsignificant difference between GIA, GIB and GIC as regards RCII, and RCIII. Using multiple linear regression analysis between respiratory chain enzymes and CPK, only RCIV showed a statistically significant correlation with CPK. Conclusions: Myopathy could be associated with alterations in respiratory chain enzyme complexes that result in effort intolerance. Such an alteration could be detected in neutrophil mitochondria by an easier noninvasive technique. RCIV could be used as a predictive marker for the occurrence of muscle damage in myopathy

Functional outcome and medicolegal implications of flexor tendon injuries at the wrist

Flexor tendon injuries at the wrist [zone V] are commonly associated with significant morbidity. Suboptimal recovery leads to residual disability with serious medicolegal impacts. To investigate the factors influencing the functional outcome of zone V flexor tendon injuries and their medicolegal aspects. Twenty patients with surgically repaired zone V flexor tendon injuries were included in the study. For each patient, flexion and extension composite range of motion of the digits as well as grip and pinch strengths were assessed before and after a supervised rehabilitation program. Data considering the place where injury took place, causative agent, time of surgery and postoperative complications and time of start of postoperative rehabilitation were recorded. Ultrasonographic evaluation was used to evaluate the status of tendon recovery at the end of the rehabilitation program. Based on assessment of digital range of motion deficit and occupation handicap, the study showed that 40% of patients recovered with less than 20% range of motion deficit, and could resume their pre-injury working ability. Sixty percent of the studied patients ended their rehabilitation program with 20% or more loss of digital range of motion with difficulty in resuming their pre-injury working abilities. The extent of tendon injury, associated nerve involvement, delay of postoperative rehabilitation and the initial base line assessment have shown significant negative correlation with the outcome measures. Multiple linear regression analysis showed that those variables were significant predictors of the final outcome measures. Ultrasound assessment revealed complete tendon healing in 40% of patients. Tendon adhesions, deficient healing and swellings indicative of infection or hematomas were demonstrated in 60% of the studied patients. It is recommended that structured supervised postoperative rehabilitation should be started promptly early postoperatively and that every effort is to be made to avoid postoperative complications. Predictors of final outcome may be used to plan and modify the program to ensure best results. Evaluation of patients' disability should be accomplished in the context of their jobs and social tasks. Determination of responsibility for settlement of compensation should consider all factors contributing to the final disability