Distal radius correction osteotomy with tricortical bone graft is a successful method in heavy smokers

Abstract

Background

Corrective osteotomy is a technically challenging surgical option to improve wrist function in tilted distal radius malunions. However fracture healing in smokers is adversely affected. The aim of this study was to evaluate the clinical and radiological effect of cigarettes on bone union in heavy-smokers who underwent corrective osteotomy with a triangular bone graft harvested from the iliac crest.

Method

Fifteen patients, who were treated using trapezoidal block grafts taken from the iliac crest, who were smokers of 20 or more cigarettes daily (heavy smokers) with no chronic disease, and who consented to participate in the study. Fifteen non-smoker patients of the same age group were determined as the control group. Radiological measurements were made to include radial inclination and ulnar variance in pre-operative and post-operative radiographs. Functional evaluation was performed using Q-DASH and MAYO hand-wrist scores.

Results

In both groups, the mean age of the patients was 49,1 ± 3,92 years. Smokers group the bone union in the osteotomy line was observed after 16,63 (12–24 h) weeks, non-smokers grup 14.1 (12–24) weeks (p = 0.06). Range of motion is found similar clinic between in groups (p > 0.05). Q-DASH for group smokers was 17.54 ± 1.85, nonsmokers 17.20 ± 1.24 (p = 0,878); MAYO was 82.27 ± 6.06 for 82.00 ± 7.74 (p = 0.874). for group B. No statistically significant difference was noted between the groups.

Conclusion

Our study showed that cigarette smoking did not have negative effect on union time in the metaphyseal region after correction osteotomy. The time of bone-union in heavy-smokers was 2.5 weeks more than that of non-smokers.

1. Introduction

Many factors such as morbid obesity, diabetes, infection, open fracture, corticosteroid or non-steroid use, and cigarette smoking negatively affect bone fracture healing. Smoking is a major problem in all societies with around 1.3 billion smokers worldwide, and this number is increasing at a high rate of 3.4% annually.¹

About 4000 harmful substances such as nicotine, carbon monoxide, and hydrogen cyanide have been identified in cigarette smoke and some of them are known to cause negative effects on bone metabolism. Nicotine disrupts the early revascularization phase of fracture healing by suppressing the transcription of factors such as fibroblast growth factor, vascular endothelial growth factor (VEGF), and bone morphogenetic protein (BMP-2-4-6), which effect angiogenesis, and osteoblast function and differentiation.² In animal experiments, nicotine was shown to reduce bone union rates and increase complications due to its negative effects on soft tissue and bone healing.³

In clinical trials, it has been shown that pseudoarthrosis develops more frequently in smokers after lumbar arthrodesis and ankle arthrodesis due to the disruption of fusions.^4,5 Similarly, in a previous study, longer bone union rates and longer bone recovery rates occurred after acute open or closed fractures in the long bone diaphysis.¹ However, to the best of our knowledge, no study has evaluated the effects of cigarette on grafting after osteotomy and corrective surgery in metaphyseal regions. The metaphyseal region is a better region with regard to blood-build-up relative to the long bone diaphysis and predictable improvement in recovery. Our aim was to investigate the effects of cigarette smoke on bone healing and functional parameters in the metaphyseal region after osteotomy and tricortical grafting in cigarette smokers.

2. Method

2.1. Study design

Clinical records of 56 patients who underwent surgery for distal radius malunion between December 2014 and November 2017 in our department were reviewed. Fifteen of these patients stated that they smoked 20 or more cigarettes daily. It was determined from their clinical records that the heavy-smoking habit continued after the surgery, and all of their follow-up procedures were performed in our hospital. We classified these 15 patients as the study group (group A). Fifteen patients, who were non-smokers, who underwent surgery in our clinic during the same period and did not have any additional disease with adverse effects on bone formation, were determined as the control group (group B). Exclusion criteria were history of former surgical operation, diabetes mellitus patients, abnormal C-reactive protein and open fracture history. Patients were reached via phone, their consent was obtained, and they were called to the hospital for final examination. Radiological measurements were made to include radial inclination and ulnar variance in pre-operative and post-operative radiographs. Functional evaluation was performed using range of motion (wrist flexion and extension, ulnar and radial deviation, forearm pronation and supination), Q-DASH and MAYO hand-wrist scores. Our study was approved by the Education and Research Hospital ethics committee, and all the parameters mentioned are measurements obtained from the patients' follow-up.

2.2. Surgical Technique

All the patients were prepared in the supine position, with one hand placed over the hand-table following anesthesia. An upper arm tourniquet was applied following venous emptying with an Esmarch bandage. An 8–10 cm incision (Henry incision) was made over the flexor carpi radialis (FCR) tendon at the volar side of the wrist. The FCR tendon was reached by subcutaneous dissection. The forearm fascia was cut at the radial border by dissection of the tendon sheath. Thereafter, the pronator quadratus muscle (PQ) was reached by a blunt dissection of the flexor pollicis longus (FPL) tendon. The PQ muscle was cut at the level of its attachment to the radius, leaving a small gap. Subsequently, finger retractors were placed on both sides of the radius, bilaterally baring the osteotomy line.

The appropriate line for osteotomy was determined, followed by the separation of the fixed angle locked distal radius plate, leaving a minimum of 3 holes in the proximal part of the osteotomy line. Osteotomy was performed at the malunion line. Next, a tricortical trapezoidal graft, whose dimensions and shape were determined preoperatively using a template, was taken from the iliac crest. The graft was adapted to the osteotomy line, which was distracted using a Chinese trap applied to the first three digits. The lesion was fixed with 2 Kirschner wires temporarily, allowing the evaluation of improvement in radial inclination, palmar tilt, and ulnar variances (UVs) under an image intensifier. After confirming the progression of the lesion under the image intensifier, the fixed angle locked distal radius plate of an appropriate size was held with screws from the first line of holes nearest to the joint (minimum of 4 screws) followed by the fixation of the proximal fragment with cortical screws. The relationship among the screws, joint, and bone cortex was evaluated under the image intensifier and the plate was covered by the PQ thereafter. The subcutaneous tissue was fixed using an absorbable suture and the skin was repaired using 3/0 prolene sutures. Surgical Technique show in Fig. 1.

Fig. 1.

Surgical technique.

2.3. Postoperative follow -up

A removable half-arm splint was applied on all patients postoperatively until soft tissue recovery was completed. Sutures were removed 15 days post-surgery. Postoperatively, patients were started on finger movements postoperative day 1 and on passive wrist movements on the 10th day. Active exercises for increasing joint range of motion and muscle strength were started after the documentation of the beginning of clinical and radiological fusion. Real antero-posterior and lateral wrist splian radiographs in addition to control antero-posterior and lateral splain radiographs were taken to evaluate the relationship between the distal screws and the joint.

2.4. Statistical analysis

Statistical evaluation was performed using SPSS 22.0 for Windows.Descriptive statistics for numerical variables were expressed as means, and standard deviation and standard error were expressed as minimum-maximum values. As normality tests for the data were performed and the number of observations was below 30, the Shapiro-Wilk “Sig” values were used to examine whether the series showed a normal distribution. To determine the relationship between groups with a normal distribution of parameters, the independent two-sample t-test was used; for parameters without a normal distribution, the Mann-Whitney U Test, a non-parametric alternative to the independent two-sample t-test, was used. The results were evaluated at a 95% confidence interval, and p < 0.05 was considered significant.

3. Results

In both groups, the mean age of the patients was 49,1 ± 3,92 years and 15 (50%) of them were female. The mean follow up was 21,8 ± 9.36 weeks (range, 12–48 weeks). Baseline demographic parameters of two groups are shown in Table 1. The correlation between age, side, gender and follow up did not differ significantly between groups (p > 0.05).

Table 1.

Baseline characteristics of the patients.

	Group 1 (n = 15)	Group 2 (n = 15)	p value
Age, mean ± SD years	50,5 ± 4,16	48,5 ± 3,32	0.821
Gender, (Female/male),	8/7	7/8	0.343
Side (Right/Left)	8/7	9/6	0.245
Follow-up	20,9 (12–36)	22,7 (12–36)	0.729

3.1. Radiological results

In group A, (UV was as follows: pre-operative 7.45 ± 0,62 (SD 2.06) and post-operative. 0.45 ± 0.41 (SD 1.36), and radial inclination (Rİ) values were as follows: pre-operative 15.18 ± 0.82 (SD 2.75) and post-operative 22.18 ± 0.74 (SD 2.48). These values were compared with those of group B [ preoperative UV value: 6.66 ± 0.50 (SD 1.95) and post-operative value: 0.00 ± 0.32 (SD 1.25); preoperative RI: 15.00 ± 0.70 (SD 2.72) and post-operative: 21.66 ± 0.83 (SD 3.22)] using independent sample test and Mann Whitney U test for UV and RI, respectively. No statistically significant difference was detected between the groups (p = 0.38) and (p = 0.68). However, the difference between preoperative and postoperative UV and RI values for the smoker group was higher than for the non-smoker group (Table 2).

Table 2.

Functional scores and radiogical outcomes of the patients comparing heavy smokers and non smokers.

	Heavy smokers	Non smokers	p value
Mayo wrist score	82,27 ± 6.06	82,00 ± 7.74	0,874
q-DASH score	17.54 ± 1.85	17.20 ± 1.24	0,878
Grip strenght	%85,00 ± 4.53	%84.73 ± 3.71	0,87
Time to union	16,63 ± 3,82 week	14.13 ± 2,82 week	0,06
Ulnar variance	0,45 ± 1.36	0.00 ± 1,25	0,38
Radial inclination	22,18 ± 2.48	21.66 ± 3,22	0,68

3.2. Functional results

All study participants were subjected to clinical scoring tests on their latest follow-up. Functional values were evaluated using MAYO and Quick-Dash symptom scores. When the two groups were compared, Q-DASH for group A was 17.54 ± 1.85 (SD6.13) whereas it was 17.20 ± 1.24 (SD 4.82) for group B; MAYO was 82.27 ± 1.82 (SD 6.06) for group A and 82.00 ± 2.00 (SD 7.74) for group B. No statistically significant difference was noted between the groups. When wrist gripping forces were compared between group A %85.00 (SD 4.53) and group B% 84.73 (SD 3.71) no statistically significant difference was found. Patients were followed-up post-operatively for an average of 20.9 (SD 7.09) months in group A and 23.0 (SD 6.3) months in group B. Radiological and functional findings are presented in Table 2.

3.3. Clinical results

According to the measurements performed at the last controls, when the average wrist and forearm movements were compared according to the extremity in the smoker group (group A), flexion was measured as −12.27 ± 2,88 (SD 9.58); extension as −13.63 ± 2.61 (SD 8.68); ulnar deviation as −5.09 ± 1.97 (SD 6.53); radial deviation as 7.27 ± 2.99 (SD 9.93); pronation as −3.63 ± 0.97(SD 3.23) and supination as −9.09 ± 2.59 (SD 8.60). Fallowingis the comporation of these measurements with those of group B: flexion −13.00 ± 2,11 (SD 8.19), extension −11.33 ± 1.65 (SD 6.39), ulnar deviation - 5.86 ± 1.19 (SD 4.61), radial deviation −5.00 ± 1.75 (SD 6.81), pronation −6.00 ± 1.70 (SD 6.60), and supination - 9.33 ± 2 (SD 9,23). Mann Whitney U test was performed because the parameters were not normally distributed, and no statistically significant difference was detected between the groups. However, in the smoker group, flexion, ulnar deviation, supination and pronation, the mean of extension and radial deviation differences were lower than those of the non-smoker group.

No statistically significant difference was noted between the groups. When wrist flexion and extension, ulnar and radial deviation, forearm pronation and supination were compared between group A and group B no statistically significant difference was found (Table 3).

Table 3.

Range of motion in wrist and forearm.

Range of motion	Differences of operated wrist functions between smoker and non-smoker groups			The differences in groups between the Operative and the Non-Operative wrists
	Heavy smokers (+SD)	Non smokers (+SD))	P value	Heavy smokers (+SD)	Non smokers ( + SD))		P value
Wrist flexion	56,36 (SD 8,68)	56,66 (SD10,76)	0,44	−12,27 (SD 9,58)		−13,00 (SD 8,19)	0,76
Wrist extension	58,6 (SD 8,39)	62,0 (SD 11,46)	0,50	−13,63 (SD 8,68)		−11,33 (SD 6,39)	0,76
Ulnar deviation	31,72 (SD 8,27)	27,8 (SD 5,04)	0,07	−5,09 (SD 6,53)		−5,86 (SD 4,61)	0,50
Radial deviation	23,63 (SD 4,71)	25,66 (SD 8,20)	0,72	−7,27 (SD 9,93)		−5,00 (SD 6,81)	0,79
Forearm supination	78,63 (SD 9,51)	81,66 (SD 8,99)	0,50	−9,09 (SD 8,60)		−9,33 (SD 9,23)	0,79
Forearm pronation	80,0 (SD 4,47)	81,66 (SD 6,72)	0,57	−3,63 (3,23)		−6,0 (SD 6,6)	0,41

During the follow-up period, two patients in the smoker group had local wound infection in the early postoperative period and recovered after oral antibiotic treatment. No further complications were observed in the patients or no implant removal was required during their follow-up visits.

4. Discussion

The most important finding of this study is that the radiological and clinical results of corrective osteotomies with tricortical bone graft in heavy-smokers were the same as those in non-smokers. Malunion is divided into three types; extraarticular, intraarticular and both. The pathology has a wide spectrum ranging from an asymptomatic deformity appearing as a simple radiological disparity, to a painful deformity severely restricting range of motion.

Angular deformity and radial shortening in the wrist cause changes in the radiocarpal and ulnocarpal joints without loading on the faces; and arthritic changes, synovitis, chronic pain, and movement limitation develop over time. However, the greatest effect on wrist function is due to radial shortening.⁶ Bronstein et al.⁷ found that 5 mm of ulnar translation reduced pronation by 23% and 10 mm of radial shortening reduced pronation by 47% and supination by 29%. Similarly, radial shortening of 15 mm or more locks the distal radioulnar joint (DRUJ) and restricts forearm rotation further. Fernandez et al.⁸ reported that a 25° radial tilt caused restriction in the flexion-extension arch. A recent study suggests that DASH scores do not fall to the level of patients who do not develop malunion even in the second year following fracture healing with positive UV and increased radial tilt. Surgical operations are recommended for these patients because of the persistent restriction.⁹

In a study comparing radial open wedge osteotomy, ulnar abbreviation osteotomy, and combined ulnar and radial abbreviation osteotomy in malunion in flexion, Saffar et al.¹⁰ suggest the use of isolated ulnar abbreviation osteotomy in geriatric patients and combined osteotomy in young people. However, Wada et al.¹¹ reported in 2004 that the reconstruction of the radial anatomy with a radial shortening of up to 15 mm returned the increased load on DRUJ to its natural state hence; no additional surgical procedure for the ulna was required. Similarly, in our opinion, the treatment algorithm, which was developed by Graham and Hastings in relation to DRUJ and its surgical treatment, which distinguished patients into four groups according to radial shortness, UV, and DRUJ compatibility, is useful.¹² Regardless of the method, the purpose of malunion surgery should be to restore anatomy and correct DRUJ incompatibility, which is the cause of restriction in forearm prono-supination.

According to the traditional dorsal open wedge osteotomy developed by Fernandez,¹³ the created defect is filled with a full thickness iliac graft. Here, grafting has two main purposes: to contribute to the mechanical stabilization of the osteotomy line with bone-to-bone support and to induce bone union. In recent years, considering the development of modern osteosynthesis techniques and the high recovery capacity of the metaphyseal region, it is said that these two functions of the cortical graft are unnecessary and successful results have been published in which grafts were not used.^14,15

We consider giving up to advantages of graft use a questionable matter. Furthermore, this decision must be left to surgeons depending on their experience and surgical preferences. In a study by Scheer et al.¹⁶ involving 15 patients, osteotomy was not supported by grafting and non-union was observed in three of the patients during follow-up visits. Subsequently, the author reported that the defect, which occurred in all non-union bones was trapezoidal and that graft support was necessary in such cases. Although Tiren achieved successful results in 11 patients who underwent corrective osteotomy with a dorsal bi-columnar double plate, hestated that the correction angle was increased in these patients and as a result, there was a delay in bone union in patients with large gaps.¹⁷ Therefore, he suggested the use of grafts in these patients. In addition, in one of their literature reviews Mugnai et al.¹⁸ found that grafting after osteotomy was not absolutely necessary, but suggested grafting in non-bone-to-bone trapezoidal gaps similar to other authors’ opinions. They also, stated that synthetic materials did not provide the same stability as cortical grafts. Ekrol et al.¹⁹ found that op-1 did not provide the same stability as iliac grafts in their study comparing op-1 with bone graft. Jepegnanam et al.²⁰ after a study in which they used injectable calcium sulfate, reported materials that can be fast-resorbed should not be used in situations where mechanical stability is required. Because the rate of resorption is higher than the rate of bone healing, implant failure developed in two of their patients.

Bone union requires a microenvironment suitable for cell differentiation and tissue formation. Healthy bone healing is possible with mechanical stability, the presence of osteogenic factors, an osteoinductive structure, appropriate growth factors, and adequate blood flow. Therefore, sufficient systemic and local conditions must be provided for fracture consolidation without problems. Thus, it is important to bear in mind while planning a surgical operation that patient-related factors, such as non-steroidal or corticosteroid use, morbid obesity, diabetes, and smoking have negative effects on bone healing. It is known that cigarette smoking particularly decreases the release of fibroblast and vascular endothelial growth factors and negates the revascularization phase, and that it has a negative effect on bone union.²¹ In a study on rats, it was found that in rats, that were exposed to cigarette smoke, prolongation of bone union duration occurred, as well as a significant decrease in callus maturity, density, and mechanical strength.²² This created a higher mechanical load on the implant and a higher risk of implant failure and depletion. Additionally, ina study by von-Houten et al.²³ 206 high tibial osteotomies (21 bilateral procedures) were performed on 185 patients and they did not use bone graft in 188 patients. From theirs study, delayed-union/non-union rates in smokers were four times higher than those of non-smokers. Chen et al.²⁴ in their study conducted on 40 patients who underwent ulnar abbreviation osteotomy, reported an average bone union duration of 7.1 and 4.1 months in smokers and non-smokers, respectively, and reported 30% delayed-union/non-union in smokers.

Non-union was not detected in any of the patients in our study (one of our patients' radiographs can be seen in Fig. 2a and b). When we compared group A and group B patients, although there was an average bone-union delay of 2.5 weeks in the patients in group A, this finding was not statistically significant. It may be considered that our results were influenced by the inadequate number of participants, but it should be noted that the distal radial metaphysis is a well-vascularized region as previously mentioned in many studies and that the bone-to-bone contact created by grafting induces bone union and biomechanical support.

Fig. 2.

a: Pre-operative anteroposterior & lateral graphy (7.months after fracture), b: Postoperative 6. Months anteroposterior& lateral graphy control graphy.

Post-operative functional parameters of the groups increased satisfactorily and no statistically significant difference was detected between the groups. Moreover, no significant difference was found between the MAYO and Q-DASH functional scores; this can be interpreted as the minimal effect of cigarette use on final functional parameters and patient satisfaction despite delay in bone union.

The most important weakness of our study is the inadequate number of patients. Additionally, the pre-operative and post-operative functional values of patients could not be compared because of incomplete pre-operative functional data. In addition, because of the retrospective nature of our study, it could not assess the correlation between the number of cigarettes smoked per day (that is to say the degree of tobacco exposure) and fracture healing. It is known that the most important metabolite that cigarettes contain is nicotine, which has a negative effect on bone union. Nicotine is metabolized to cotinine in the liver and can be used as a marker to assess the level of tobacco exposure due to its long half-life. Through a prospective study, the correlation between the number of cigarettes smoked in a day and bone healing can be evaluated. Another aspect of our study that we may consider as a weakness is the lack of a group of patients who were not operated on using synthetic graft material to fill the defect or who did not receive grafts. However, in our opinion, the non-use of grafts is too risky considering the work of Sheer et al.¹⁸

5. Conclusion

The bone-union rates in corrective osteotomies with triangular bone graft are generally high, with good clinical and functional results. The same clinical and radiological succes can be archieved in heavy-smokers as like as non-smokers even when the iliac wing graft is used. Whether the defect created in the osteotomy line is triangular or trapezoidal, bone-to-bone contact must be ensured in patients who smoke cigarettes. We suggest that the classic method can be applied with less risk of discomfort and high functional success rate in this specific group of patients, although many successful studies that applied osteotomy without using grafts exist in the literature.

Disclaimer

The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.

Appendix A. Supplementary data

The following is the Supplementary data to this article: