Local flap therapy for the treatment of pressure sore wounds

Abstract

The aim of this study was to analyse the effectiveness of an interdisciplinary cooperation between conservative and surgical disciplines for the treatment of pressure sores (PS). From January 2004 to December 2005, a single‐centre study was performed with paraplegic and tetraplegic patients presenting with PS grades III–V. Outcome measures were defect size, grade, method of reconstruction, complication and recurrence rate as well as average length of hospitalisation. A total of 119 patients aged 22–84 years with totally 170 PS were included. The most common PS were located in the ischial region (47%), followed by the sacral (18%), trochanteric (11%), foot (9%) and the malleolar (8%) regions. Defect sizes ranged between 4 and 255 cm². Grade IV was the most common PS (68%), followed by grade III (30%) and grade V (2%) PS. For wound closure, fasciocutaneous flaps were used most frequently (71%), followed by skin grafts (10%) and myocutaneous flaps (7%). Postoperative follow‐up ranged between 6 and 38 months. The overall complication and recurrence rate was 26% and 11%, respectively. If no complication occurred, the average duration of hospitalisation stay after the first debridement was 98 ± 62 days. In conclusion, our treatment concept is reliable, effective and results in a low recurrence rate. The complication rate, even though favourable when compared with the literature, still needs to be improved.

Introduction

Paraplegic and tetraplegic patients are at high risk of developing pressure sores (PS). The lifetime incidence of PS ranged between 52% and 86% with a higher incidence among tetraplegic patients 1, 2. PS not only significantly reduces the quality of life but also may be life threatening 3, 4.

There are multiple intrinsic and extrinsic aetiological interacting factors 5, 6, of which immobility and loss of sensibility combined with shearing and direct pressure are the most significant ones 7, 8. Among the intrinsic factors, malnutrition, anaemia and hypoproteinaemia can favour the development of PS 9. Other important contributing factors include lack of proximate family support, social isolation and poverty 10.

The majority of PS occur over the sacrum and coccyx, ischium and greater trochanters 11. The surgeon is usually faced with advanced grade III to grade IV PS 6, 12 requiring surgical management 13.

Since the report by Conway and Griffith in 1956, the fundamental surgical principles for the management of PS remain essentially unchanged 14 and consist of debridement of the ulcer, underlying bursa and involved bone followed by wound conditioning and soft‐tissue coverage. For defect closure, a multitude of different flaps have been described 15, 16, 17, 18, 19. In the paraplegic patient group, an important consideration should be given to recurrence, that is, local tissue should be used with forethought of subsequent flap procedures.

At the Swiss Paraplegic Center (SPZ, Nottwil, Switzerland) there is an intense interdisciplinary collaboration between rehabilitation and plastic surgery with a strict rehabilitation program that has been elaborated over the past years. Thus, the aim of the study was to analyse and compare the results of a consecutive series of 170 PS.

Materials and methods

A retrospective analysis was performed at the SPZ Nottwil. All patients with PS grades III–V according to Daniel and Seiler 6 and operated between January 2004 and December 2005 were included. Written informed consent was obtained from all patients.

SPZ interdisciplinary treatment protocol

The initial patient evaluation was performed together by a plastic surgeon and a physician from the rehabilitation team in order to define the best treatment schedule. The principles 6, 20, 21, 22 described by Seiler were as follows: (i) avoidance of pressure, (ii) radical debridement of the necrotic tissue in the no‐touch pseudo‐tumour technique 23, (iii) conditioning of the wound and treatment, respectively, (iv) elimination of the risk factors including malnutrition, (v) defect closure and (vi) PS prophylaxis with training programs. Analyses of the blood samples were performed routinely to detect signs of infection and if bone was exposed, biopsies were taken during surgery for histological and bacteriological analyses. Radiological imaging (computed tomography, magnetic resonance imaging and sonography) was not routinely performed. Postoperative management after flap reconstruction occurred in a standardised manner (Table 1) 6. Two drains were used in all flap patients: one of them was left for 2 weeks and the other was removed if output was <20 ml/24 hours. For primary PS without osteomyelitis, strict immobilisation was applied for 4 weeks on a KCI mattress. Passive hip flexion until 30° for 30 minutes was started on week 3 without undue tension on the scar or flap, followed by a strictly scheduled mobilisation program in the wheelchair 4 weeks after the surgery. If the scar conditions were stable after daily mobilisation of 2 × 4 hours in the wheelchair, patients were discharged. For secondary PS or osteomyelitis, strict immobilisation was applied for 6 weeks. All patients were hospitalised in the rehabilitation clinic and flap healing was regularly assessed by a plastic surgeon together with the rehabilitation team and documented weekly by digital imaging. The first outpatient follow‐up visit was scheduled 6 months after discharge and then every year.

Table 1.

Postoperative standard mobilisation procedure for primary pressure sore

Week	Activity/Mobilisation
1–3	Strict immobilisation with permitted passive hip flexion until 30° for a maximum of 30 minutes without undue tension on the scar/flap. Day 14 removal of the drainage.
3	Removing stitches. Start with scar massage and passive mobilisation of lower extremity by physiotherapy.
4	Start with 2 × 30 minutes/day, then increasing daily 30 minutes until full mobilisation (2 × 4 hours). Mobilisation in wheel chair as soon as passive hip flexion of 90° without tension was achieved.

Demographics

Patient age, gender and level of plegia were recorded in a standardised manner. For the outcome analysis of the flap procedures, patient charts were reviewed for diabetes mellitus.

Intraoperative data and postoperative follow‐up

PS were labelled as either primary or secondary PS. Localisation, size and grade of the defects as well as the interval between debridement and defect coverage were recorded. The method of reconstruction in terms of flap pedicle and tissue composition was assessed. Postoperative flap‐related complications such as haematoma, infection, seroma, wound dehiscence and partial flap necrosis were assessed and classified as minor or major complications, depending on whether a reoperation was necessary or not. The average length of hospitalisation and the recurrence rate were analysed.

Surgical technique

In primary PS, fasciocutaneous flaps are preferentially used for defect coverage, that is, medially pedicled posterior thigh flaps for ischial PS, lateroinferiorly pedicled gluteal rotation flaps for sacral PS (Figure 1) and lateral thigh flaps for trochanteric PS. The flaps are designed to keep the scars outside the primary pressure zones. During flap mobilisation, as many perforating vessels as possible were preserved. For flap inset, deep anchoring sutures were used at the tip of the flap 24. This was followed by layered closure of the superficial fascia, dermis and Donati‐type skin closure. Two drains were routinely used: one to prevent infection directly over the PS and the other to drain postoperative wound fluid. For gluteal rotation flaps, the donor site was closed directly and for large ischial and trochanteric PS, skin grafts were used to cover the distal part of the donor site if necessary.

Figure 1.

(A) Representative image of a 75‐year‐old female patient after debridement of a sacral pressure sore grade V with osteomyelitis. (B) Image showing the postoperative situs after defect closure with a fasciocutaneous gluteal rotation flap.

Statistical analysis

All presented data are expressed as mean ± standard deviation (SD). Contingency χ ² test and relative risk (RR) were performed to investigate whether the type of flap, osteomyelitis, diabetes mellitus, primary PS or secondary PS were influencing the percentage distributions of postoperative complication or recurrence rate (GraphPad Prism 5.0, San Diego, CA). All statistical tests were two‐sided and analysed at an alpha level of 0·05. The confidence level was set at 95%.

Results

A total of 119 consecutive patients (91 males and 28 females) with a total of 170 PS were included. Mean age was 51 years (range 22–84 years). Of these, 74 patients (62%) were paraplegic and 27 were tetraplegic (23%), and the other patients were diagnosed either with spina bifida, muscular dystrophy or multiple sclerosis. There were 111 (65%) primary PS and 59 (35%) secondary PS. Grade IV was the most common PS (68%, 116/170), followed by grade III (30%, 50/170) and grade V (2%, 4/170) PS. Eighty‐four bone biopsies were taken; of these 26 (31%) were positive for osteomyelitis. The most common PS were located in the ischial region (47%), followed by the sacral (18%) and trochanteric regions (11%) (Figure 2). The sizes of the PS ranged between 4 and 255 cm². The mean sizes for the sacral, ischial and trochanteric PS after debridement and before flap reconstruction were 78 ± 74, 24 ± 17 and 22 ± 5 cm², respectively. The mean time from debridement to defect closure was 40 ± 22 days and the average length of hospitalised bed rest after flap coverage was 58 days. Postoperative follow‐up ranged between 6 and 38 months. Twenty‐three patients died during the study period.

Figure 2.

Overview of the anatomic pressure sores.

For wound closure, the fasciocutaneous flaps were most frequently used (not including perforator flaps) (71%, 121/170), followed by skin grafts (10%, 17/170), myocutaneous flaps (7%, 11/170), perforator flaps (6%, 10/170), direct closure (4%, 7/170) and four others (2%, 4/170) (Figure 3). Perforator flaps, even though fasciocutaneous flaps, are considered separately because they have the drawback of islanded flaps that permit only limited secondary advancement.

Figure 3.

Overview of the most commonly used methods to cover defect size.

Complication rate

Overall, 44 complications occurred (26%). There were 25 partial necroses and wound dehiscences (15%), 11 haematomas and seromas (6%) and 8 abscesses/infections (5%). A higher but not significant complication rate was found in sacral and ischial PS (35% and 32%, respectively) compared with trochanter PS (26%). There were 27 (16%) major complications, which required surgical revision. Although not significant, more complications were found among paraplegic patients, defect closures with myocutaneous flaps, secondary PS and patients diagnosed with diabetes (Table 2). In case of an osteomyelitis, there was a significant higher complication rate (P = 0·002, RR 2·9). In case a complication occurred, the duration of hospitalisation was significantly delayed (98 ± 62 versus 137 ± 57 days; P < 0·0001).

Table 2.

Complication rate with regard to morbidity, type of defect closure, primary versus secondary pressure sore, osteomyelitis and diabetes

	Complication	No complication	P‐value; RR (CI)
Tetraplegic (N/%)	6 (22)	21 (78)	0·94; 0·97 (0·4–2·2)
Paraplegic (N/%)	17 (23)	57 (77)
Myocutaneous flap (N/%)	5 (45)	6 (55)	0·06; 2·2 (1·0–4·6)
Fasciocutaneous flap (N/%)	25 (21)	96 (79)
Primary pressure sore (N/%)	21 (19)	90 (81)	0·32; 1·3 (0·7–2·4)
Secondary pressure sore (N/%)	15 (25)	44 (75)
Osteomyelitis (N/%)	13 (50)	13 (50)	0·002; 2·9 (1·5–5·7)
No osteomyelitis (N/%)	10 (17)	48 (83)
Diabetes (N/%)	5 (31)	11 (69)	0·54; 1·3 (0·6–2·8)
No diabetes (N/%)	33 (24)	103 (76)
Hospitalisation (days ± SD)	137 ± 57	98 ± 62	<0·0001; 2·25 (1·7–3)

RR, relative risk; CI, confidence interval; SD, standard deviation.

Recurrence rate

During the study period, the recurrence rate was 11% (19/170). In line with the complication rate, there was a higher recurrence rate among paraplegic patients, defect closure with myocutaneous flaps and secondary PS (Table 3). In case of recurrence there was a significant delay in hospital discharge.

Table 3.

Recurrence rate with regard to morbidity, type of defect closure, primary versus secondary pressure sore, osteomyelitis and diabetes

	Recurrence	No recurrence	P‐value; RR (CI)
Tetraplegic (N/%)	2 (7)	25 (93)	0·6; 0·7 (0·2–3·0)
Paraplegic (N/%)	8 (11)	66 (89)
Myocutaneous flap (N/%)	2 (18)	9 (82)	0·71; 1·3 (0·3–4·9)
Fasciocutaneous flap (N/%)	17 (14)	104 (86)
Primary pressure sore (N/%)	11 (10)	100 (90)	0·47; 1·4 (0·6–3·2)
Secondary pressure sore (N/%)	8 (13)	51 (87)
Osteomyelitis (N/%)	3 (11)	23 (89)	0·1; 0·4 (0·1–1·3)
No osteomyelitis (N/%)	16 (17)	42 (83)
Diabetes (N/%)	1 (6)	15 (93)	0·25; 0·36 (0·05–2·5)
No diabetes (N/%)	18 (17)	85 (83)
Hospitalisation (days ± SD)	119 ± 37	98 ± 62	<0·0001; 4·9 (3·2–7·6)

RR, relative risk; CI, confidence interval; SD, standard deviation.

Discussion

As of today the treatment of PS remains a clinical challenge; a highly collaborative team approach for risk assessment, prevention and treatment is vital for an optimal outcome. In addition, considering the staging of reconstruction, the time of bed rest and hospitalisation postoperatively combined with a correction of the underlying risk factors are key factors to improve outcome and reduce overall health costs.

Debridement is considered as the cornerstone for treating contaminated PS 11. If the wound is inadequately debrided before reconstruction, it will lend itself to failure 17. In the present series, the average wound conditioning interval between debridement and defect reconstruction was 40 days. Only 1% of patient required a secondary debridement. The average length of hospitalisation after flap coverage was 58 days, which is longer than that reported in other studies 25, 26. However, the complication rate with 26% was relatively low, especially if one considers the major complication rate of only 16% requiring a reoperation. In line with these results, the recurrence rate of 11% was also low compared with the literature. A significant longer hospitalisation stay was observed when a complication or recurrence occurred. Yet, there remains room for improvement.

Flap reconstructions are associated with a high operative (17–36%) and overall (28–42%) complication rate such as wound dehiscence, partial flap necrosis and seroma and fistula formation 18, 19, 27, 28. The application of fibrin glue in fasciocutaneous flap surgery for pressure sore coverage has been shown beneficial 29. The recurrence rate of ulcers at the same site was reported to be 19–33% 28, 30. Recurrences were noted of 22% and 15% in primary and secondary lesions, respectively 30. Finally, the number of readmitted patients developing an ulcer at a new site is shown to be 22–25% 28, 30.

It might be that the relatively low complication and recurrence rate of this series is the result of a hospital that exclusively takes care of paraplegic and tetraplegic patients and that provides global care of the patient (medical, psychological and professional reintegration). Furthermore, postoperative guidelines, which were elaborated over the last 20 years, were strictly followed.

A high complication rate has tremendous economic implications because in today's cost‐effective managed care environment long‐term recurrence rates should be as low as possible 18. Although the interdisciplinary team approach can only marginally influence the rate of surgical complications, the low recurrence rate may be a direct benefit of the intense patient monitoring and education combined with technical support in daily activities.

In our study, the fasciocutaneous flap was the most commonly used flap for defect closure. It has been suggested that the fasciocutaneous flap provides a higher mechanical resistance than the detached and transposed muscle 17. The design of the fasciocutaneous rotation or transposition flaps should be generous, because non‐propeller or non‐islanded fasciocutaneous flaps can easily be reused in case of recurrence. A salvage procedure in recurrences is the combined muscle and fasciocutaneous tissue mobilisation.

In this series, there was a strong correlation of osteomyelitis and postoperative complication rate, whereas no significance has been found among patients with diabetes mellitus, primary versus secondary PS or paraplegic and tetraplegic patients with regard to complication and recurrence rate. Nevertheless, there was a trend towards a higher complication and recurrence rate after defect closure with a myocutaneous flap and among patients diagnosed with secondary PS. This might be due to the fact that myocutaneous flaps were used in more complicated situations where fasciocutaneous flaps have been used before and did not allow for secondary flap rotation due to scar position or size of the PS.

In future, the identification of factors that permit the prediction of a successful debridement may lead to a one‐stage debridement and flap closure. Postoperatively, prolonged immobilisation in the bed and late suture removal are important factors in surgical success among nutritional and medical status rehabilitation, and spasticity control 31.

Conclusions

Apart from careful flap selection, an interdisciplinary approach with regard to comorbidities, expectations and psychosocial factors is mandatory to achieve optimum rates of healing. Our concept is a reliable and effective model for the treatment of PS, leading to a low overall complication and recurrence rate.