The growth factors involved in flexor tendon repair and adhesion formation.

Flexor tendon injuries remain a significant clinical problem, owing to the formation of adhesions or tendon rupture. A number of strategies have been tried to improve outcomes, but as yet none are routinely used in clinical practice. Understanding the role that growth factors play in tendon repair should enable a more targeted approach to be developed to improve the results of flexor tendon repair. This review describes the main growth factors in tendon wound healing, and the role they play in both repair and adhesion formation.

In vitro flexor tendon cell response to TGF-beta1: a gene expression study.

PURPOSE: Adhesion formation around zone II flexor tendon repairs remains an important clinical challenge. Tendon healing is complex, and when uncontrolled it may lead to adhesion formation. Transforming growth factor-beta1 (TGF-beta1) is a multipotent growth factor known to be involved in wound healing and scar formation. It has also been shown to have a role in both tendon healing and adhesion formation. METHODS: Uninjured rabbit flexor tendons were divided into endotenon, epitenon, and sheath cells and cultured separately. The in vitro effect of TGF-beta1 gene expression was determined on quiescent tendon cells using real-time polymerase chain reaction for collagen type 1, collagen type 3, fibronectin, plasminogen activator inhibitor-1 (PAI-1), and tissue plasminogen activator (t-PA). RESULTS: Endotenon-derived cells showed a statistically significant down-regulation of collagen type I gene expression in response to TGF-beta1 compared with untreated endotenon cells and with both epitenon and sheath cells at a number of time points. However, endotenon cells showed an increase in collagen type 3 gene expression compared with untreated cells and epitenon cells. All cells showed a statistically significant increase in fibronectin in the later time points compared with the untreated cells. Endotenon-derived cells showed an early increase in PAI-1, whereas sheath cells showed a later increase. CONCLUSIONS: We have shown that cells cultured from 3 separate parts of the flexor tendon-sheath complex respond in different ways when stimulated with TGF-beta1. The down-regulation of collagen types 1 and 3 in endotenon cells may give further insight into the effects of TGF-beta1 in tendon healing. Also, the upregulation of fibronectin and PAI-1, combined with a down-regulation of tissue plasminogen activator, could explain the association of TGF-beta1 with tendon adhesion formation. Treatments aimed at improving tendon healing and the prevention of adhesions may arise from modification of the effects of TGF-beta1.

Resuscitation tables: a useful tool in calculating pre-burns unit fluid requirements.

BACKGROUND: There is considerable variation in the standard of initial burn management, particularly burn surface area assessment and application of resuscitation formulae. Early aggressive management of major burns improves survival. Internationally, the Parkland formula employing lactated Ringer's solution is used for fluid resuscitation. This study aimed to assess whether Parkland fluid resuscitation tables could improve the accuracy of initial fluid requirement calculations. METHODS: The burn size had first to be determined for an adult and a child using a preshaded Lund and Browder chart. Fluid requirements then had to be calculated using the conventional Parkland formula. The burn size had to be similarly calculated for two further cases and fluid requirements calculated using resuscitation tables. The study had a sample size of 50, consisting of plastic surgery trainees, anaesthetists and burn nurse specialists. RESULTS: All the participants found the resuscitation tables to be quicker and easier to use. The burn size was correctly calculated in 72% of cases. Fluid resuscitation requirements were correct in only 55% when using the Parkland formula. The use of resuscitation tables improved the accuracy in calculating fluid requirements to 75%. CONCLUSIONS: The use of Parkland fluid resuscitation tables can improve accuracy and ease of calculation of fluid resuscitation requirements.

Transforming growth factor beta1 signalling, wound healing and repair: a multifunctional cytokine with clinical implications for wound repair, a delicate balance.

Transforming growth factor beta1 (TGFbeta1) is a multifunctional cytokine known to be involved in a number of human diseases. It is believed to play an important role in wound healing and repair, as it is a key regulator of the production and remodelling of the extracellular matrix through its effect on mesenchymal cells. Over the last few years, it has become evident that the signalling pathway of TGFbeta is complex with numerous receptor-ligand interactions, intracellular pathways and a number of mechanisms, which not only control the signalling but may also decide the response to the TGFbeta signal. This review focuses on TGFbeta1 signalling and the role that TGFbeta1 plays in wound healing, repair and scarring.

Stanmore total knee replacement versus internal fixation for supracondylar fractures of the distal femur in elderly patients.

BACKGROUND: Supracondylar fractures of the femur in the elderly are difficult to treat. Total knee replacement is often not considered. The aim of this study was to compare the short to medium term outcome of fixation and total knee replacement in medically fit active elderly patients with no pre-existing arthritis in order to determine whether total knee replacement can be an alternative to internal fixation. PATIENTS AND METHODS: In this retrospective study, we included patients who were aged 75 or over with an ASA grade of two or less, walked independently before their injury, and sustained a type A or C supracondylar fracture. Four were treated with internal fixation and six with a cemented Stanmore knee replacement. Patients were reviewed clinically and radiographically a minimum of 6 months after surgery. RESULTS: The advantages of total knee replacement were a greater proportion of patients returned to independent walking, rehabilitation was more rapid, and knee flexion was better. The advantages of internal fixation were a decreased need of blood transfusion, a smaller proportion of patients reported knee pain at follow up, and a better mean Oxford knee score at follow up. Anaesthetic time and level of patient satisfaction at follow up were similar. There were no peri-operative deaths. CONCLUSION: In this preliminary study, total knee replacement was a reasonable alternative to internal fixation for the treatment of supracondylar fractures of the distal femur in elderly.

Surgical correction of ventricular septal defects in black and white children--an 11-year study.

The clinical and ECG features, anatomical subtypes and outcome in 309 children (169 black; 140 white; 58% female) who underwent surgical closure of ventricular septal defects (VSDs) are presented. Clinical presentation was more severe in the black children; with recurrent pulmonary infections in 65% blacks compared with 34% whites. Congestive cardiac failure was noted in 60% blacks and in 37% whites. At cardiac catheterisation a left to right shunt greater than 2.5/1 was found in 45.5% of the black and in 39.3% of the white children. Severe pulmonary hypertension (greater than 80% of systemic systolic pressure) was evenly distributed in both groups. Of the 140 white children, 74.3% underwent surgery under the age of 2 years compared with 68.6% of the 169 blacks. A perimembranous VSD was found in 65% of patients in each group. Infundibular (muscular outlet) defects were observed in 28.6% of white and 30.8% of black children. Left axis deviation (LAD) on ECG was found in 11.9% of white and 9.2% of black patients; and 93% of the total of 27 cases had a perimembranous defect. Early mortality was 3.6% in white and 7.1% among the black children. Of the 17 fatal cases in the total group, 16 had severe pulmonary hypertension. It is concluded that: (i) operative results compared favourably with those reported elsewhere; (ii) the anatomical subtypes occurred with equal frequency in both ethnic groups; and (iii) this was also the case for LAD on ECG, which was most commonly associated with a perimembranous VSD.