Factors Affecting Frozen Shoulder Capsular Release ...

z3432211 – Ahmed Jamal Harisha

14 October 2016

St George Hospital Orthopaedic Research Institute

Factors Affecting Frozen Shoulder Capsular Release Outcomes 4696 words excluding abstract, headings and figures. (Abstract: 250 words)

Ahmed Jamal Harisha, Patrick H Lam, George AC Murrell

UNSW ID 3432211


Abstract Background: Arthroscopic capsular release has demonstrated good short-term and long-term outcomes in patients with frozen shoulder. It is unclear if there is a relationship between timing of surgery and functional outcomes; and which subsets of patients have the best outcomes and are most suitable for surgery.

Method: The study retrospectively evaluated 189 shoulders with idiopathic adhesive capsulitis who underwent an arthroscopic capsular release. All patients had completed the modified L’Insalata questionnaire prior to surgery. Shoulder function and patientreported pain scores were evaluated using Likert scales, whilst range of motion and strength was examined at 1 week, 6 weeks, 12 weeks and six months postoperatively by an independent examiner.

Results : Preoperative and intraoperative external rotation, showed that the shorter symptoms cohort were more restricted than the longer symptoms cohort; (22° ± 18° vs. 34° ± 21°) (P = .0038), and (17° ± 17° vs. 27° ± 27°) (P = .03) respective ly. Postoperative internal rotation showed a greater improvement in the shorter symptoms cohort six months after surgery; (T11 ± 5 vertebral levels vs. L2 ± 6) (P = .02). The variables with the most independent effect to predict the change in external rotation six months after surgery were: P = 84.203 - (0.699 x age at surgery in years) - (0.969 x preoperative external rotation in °) + 1.888 x preoperative internal rotation in number of vertebral levels).

Conclusion: Capsular release has proven to be beneficial in patients with a shorter duration of symptoms. Preoperative external rotation, preoperative internal rotation and age at surgery have all shown the greatest association in predicting the change in external rotation six months after surgery.


Introduction Idiopathic adhesive capsulitis or frozen shoulder, is a condition characterised by the unprompted onset of long lasting pain and limited global range of motion in the shoulder1-3 . There is an estimated prevalence between 2% to 5% in outpatient clinics 4 . The aetiology of the condition is not fully understood. Women are commonly more affected than men at a ratio of 1.4:1, with peak onset at between 50 – 55 years5 . The classic timeline of adhesive capsulitis occurs in 3 continuous phases. The first, or freezing phase is characterised with severe pain and stiffness in the affected shoulder and is predominantly worse at night. The second, or frozen phase presents with significant reduction in glenohumeral movements, most noticeably in external rotation. The final, or thawing phase involves gradual resolution and improvement in range of motion. The process can take anywhere from 2 to 3 years to resolve; but symptoms may persist long-term6 . Treatment of adhesive capsulitis is homogenous, and aimed at total restoration of the shoulder.

Non-operative

interventions

include

non-steroidal

anti-inflammato r y

administration, physical therapy and intra-articular steroid injections7 . The short term benefits from these methods are good but recovery has not been shown to accelerate8 . Surgical interventions include, an open release, manipulation under anaesthesia, or an arthroscopic capsular release. Complications such as haemarthrosis and capsule tears have been noticed with the manipulation9,10 . The controlled fashion of the arthroscopic release aligns with speculation that is safer than other surgical methods 3,11 . We have previously seen that arthroscopic capsular release for idiopathic adhesive capsulitis is a beneficial mode of treatment and results in the reduction of pain severity, frequency and increased range of motion in the short and long term (as long as 13 years) 6,12 . No studies have addressed if there is a relationship between timing of surgery and

z3432211 – Ahmed Jamal Harisha functional outcomes; specifically range of motion, patient-ranked stiffness and overall patient-ranked shoulder satisfaction. It is unclear at which of the three phases of adhesive capsulitis, capsular release is most beneficial. Several studies have shown that patients demonstrate good outcomes6,13-15 , but there is no evidence as to which subsets of patients have the best outcome, and therefore the most suitable for surgery. Hence, the purpose of this study was (1) to identify if arthroscopic capsular release is beneficial in the first phase of idiopathic adhesive capsulitis, and (2) to assess which subsets of patients are most suitable for surgery by producing predictive formulas for the change in functional outcomes, six months after surgery.

Materials and methods Study design Our hypothesis was that capsular release undertaken during the early symptomatic stage, otherwise known, as the freezing phase of idiopathic adhesive capsulitis would provide a swift reduction in pain, stiffness in shoulder function and improved range of motion in patients with results comparable to patients who underwent the release at a later stage. A retrospective study was performed of patients who had an arthroscopic capsular release for adhesive capsulitis by the senior author (G.A.C.M). The aim of the study was to identify which patients had the greatest functional recovery of the shoulder joint 6 months after the release. The primary outcome measured was the change in external rotation of the shoulder at 6 months following the capsular release. Other primary outcomes consisted of the change in patient ranked stiffness scores and the change in-patient reported overall shoulder satisfaction. Secondary outcomes includ ed examiner- determined range of motion (abduction, internal rotation, and forward flexion) and strength (adduction, external rotation, internal rotation, subscapularis and

z3432211 – Ahmed Jamal Harisha supraspinatus). Patient-reported outcomes comprised of changes in frequency of activity pain, resting pain and extreme pain; degree of rest pain, overhead pain, and sleep pain; difficulty with shoulder motion above the head, and degree of activity at work and amount of sport played at 1 week, 6 weeks, 12 weeks, and 6 months following surgery.

Inclusion and exclusion criteria Patients were included in the study if a clinical diagnosis of idiopathic adhesive capsulitis was made, with which the criteria used were a painful, stiff shoulder; restriction in passive range of motion (especially external rotation) and a loss in function; pain at rest and that disturbed daily activities and sleep with no other identifiable cause11,16,17. Patients included in this study must have been examined at clinic and consented to surgery for an arthroscopic capsular release performed by the senior author. They must also have attended 1 follow-up clinic at the minimum. Patients were excluded if the affected shoulder had; a prior fracture to surrounding structures, a previous rotator cuff repair, grade II or greater joint arthritis, calcific tendinitis, previous surgery to the shoulder, or previous sepsis around the shoulder.

Outcome assessment Prior to each consultation (preoperative evaluation and 1 week, 6 weeks, 12 weeks and 6 months of follow up), every patient completed a standardised questionnaire assessing shoulder function

and pain (based on the L’Insalata

Score Shoulder Rating

Questionnaire)18 . The questionnaire used a Likert scale to answer questions regarding the frequency of pain during activities, sleep and when its extreme (always, daily,

z3432211 – Ahmed Jamal Harisha weekly, monthly, never) and degree of pain during sleep, activities and at rest (very severe, severe, moderate, mild, none). Activities behind the back and overhead were also ranked with this scale. Additional Likert scales were used to grade patient determined shoulder stiffness (very, quite, moderately, a little, not at all), overall shoulder satisfaction (very bad, bad, poor, fair, good), and current level of work (none, light activity, moderate activity, strenuous labour) and sport (none, hobby sport, club sport, national sport). Examiners utilised a previously validated procedure to measure passive range of motion and strength at each clinical visit (apart from 1 week after surgery)19 . Passive range of motion (abduction, external rotation, forward flexio n, internal rotation) was evaluated visually. Strength (adduction, external rotation, interna l rotation, subscapularis, supraspinatus) was evaluated using a hand-held force gauge (HFG 110, Transducer Techniques, Temecula, California, USA).

Operative procedures and rehabilitation Arthroscopic capsular release was carried out in a day surgical setting. Patients undergoing the procedure underwent interscalene regional anaesthesia and positioned in the beach-chair position. Intra-operative shoulder range of motion was noted and documented, the patient was prepared and draped, and a posterior portal was made for glenohumeral arthroscopy. After the joint was examined with the arthroscope, a spinal needle was introduced through an anterior portal, just lateral to the coracoid process. The spinal needle ensured access for the instruments to the posterior and inferio r aspects of the capsule. The anterior portal was then made superior to the upper border of the subscapularis tendon. Through the anterior portal, the tissues in the rotator cuff interval, from the anterior border of the long head of the biceps to the coracoid are excised and released (using a CoVac 50 ArthroWand; ArthroCare, Sunnyvale, CA,

z3432211 – Ahmed Jamal Harisha USA). The intra-articular segment of the subscapularis tendon was also released. The capsule was then cut anterior-inferiorly, just lateral to the glenoid labrum. The spinal needle was used again to establish a posterior-inferior portal, which was subsequently released. The result was a 360° capsular release. The shoulder was manipulated and stabilised so the arm could be visually assessed to test the new range of motion; 10mL of Depo-Medrol with lidocaine (40mg/mL methylprednisolone acetate and 10mg/mL lidocaine hydrochloride, with 0.9% m/v benzyl alcohol) was introduced into the joint. The portals were sutured, and a large dressing was then applied. A sling was not provided for the patient in order to encourage the postoperative rehabilitation regime n. The patient met with a physiotherapist on day one, with the intention of maintaining active and passive shoulder motion. The patient was advised to repeat the exercises every 2 hours for the remainder of the week until the next clinic visit. The patient was also instructed to perform 12 repetitions of assisted external rotation movements with a broom lever. During the second week, patients were advised to begin at least three sets of exercises every day using a TheraBand (Hygenic, Akron, OH, USA). Patients also began to perform rotator cuff strengthening exercises. Patients were advised to carry out this routine 3 times per day, for 12 weeks.

Statistical analysis Outcomes with parametric data were analysed by using 2-way unpaired Student t tests and non-parametric data with GraphPad Prism 5.0 software (GraphPad Software, La Jolla, California, USA), to analyse the variance in two groups with a normal distribution. Spearman rank correlation tests were also performed to assess the relationship between the distributions. Results were considered significant if P ≤ .05.

z3432211 – Ahmed Jamal Harisha Multiple logistic regression analyses were performed using SigmaPlot software (Systat Software, San Jose, California, USA), with the primary dependent variable defined as the change in external rotation from the preoperative clinic visit to 6 months after the capsular release and the independent variables included patient and surgical factors, preoperatively and intra-operatively. The other dependent variables investigated were the change in patient ranked stiffness scores and the change in overall shoulder satisfaction from the first preoperative visit to 6 months after the capsular release. The preoperative variables recorded were patient age in years, gender, side of affected shoulder, duration of symptoms, and passive range of shoulder motion (abduction, external rotation, internal rotation, forward flexion). The intra-operative variables included operative time, if manipulation under anaesthesia was performed, intra operative passive range of motion under anaesthesia (abduction, external rotation, internal rotation, forward flexion).

Results Study group From January 2001 to December 2015, the senior author performed 297 arthroscopic capsular releases for adhesive capsulitis of the shoulder in 280 patients. Of these 297 capsular releases, 15 operations met the exclusion criteria due to simultaneous rotator cuff repair surgery, 63 patient records had insufficient data and 30 patients failed to attend at least 1 follow-up clinic at six months’ post-surgery. Eight patients had capsular releases on both shoulders at separate times. The study cohort thus comprised of these 189 procedures.


Cohort demographics The study consisted of 120 women (63%) and 69 men (37%) with a mean age of 55 ± 8 (mean ± standard deviation) years (range, 24-80 years). The mean duration of symptoms was 10 months (range, 1-364 months). Eight patients underwent a manipulation under anaesthesia before the capsular release and this was deemed adequate to regain range of motion without additional surgical intervention. Of the 189 operations, 105 (56%) were on the left side and 84 (44%) were on the right. The mean operative time was 30 minutes (range, 3-120 minutes).

The 189 patients were split into 3 different groups based on their duration of symptoms. 131 patients indicated their duration of symptoms to be less than 10 months before surgery. 17 patients indicated their duration of symptoms to be between 10 and 16 months before surgery and 21 patients indicated their symptoms to have lasted longer than 16 months before surgery. 20 patients failed to specify their length of their symptoms and were excluded. Due to insufficient data for analysis, the latter two groups were combined to make 38 patients with symptoms lasting longer than 10 months. The first group with 131 patients consisted of 79 (60%) women and 52 (40%) men with a mean age of 56 ± 8 (mean ± standard deviation) years. The mean duration of symptoms was 4 ± 2 months, (range, 0-9 months). The second group of 38 patients consisted of 27 (71%) women and 11 (29%) men with a mean age of 55 ± 7.5 years. The mean duration of symptoms was 32 ± 57 months (range, 10-364 months). Operative time was not significant between the two groups (P = .47).


Preoperative analysis The trademark sign of adhesive capsulitis is the restriction in all planes of movement in the glenohumeral joint. Preoperative measures were assessed using unpaired Student’s t tests to compare the significance between the cohort with the shorter duration of symptoms and the cohort with the longer duration of symptoms. The group with the shorter duration of symptoms had a mean preoperative external rotation range of 22° ± 18° (mean ± standard deviation) and the group with the longer duration of symptoms had a mean preoperative external rotation range of 34° ± 21°, and found to be statistically significant (P = .0038). A similar pattern was seen in all other ranges of motion, apart from internal rotation. Forward flexion had a mean preoperative range of 97° ± 31° in the first cohort and 106° ± 33° in the second cohort, (P = .15). Abduction had a preoperative mean of 79 ± 32° in the first cohort and 84° ± 38° in the second cohort. Internal rotation had a mean preoperative range of S2 ± 4 vertebral levels in the first cohort and S2 ± 4 vertebral levels in the second cohort. The patient-ranked stiffnes s preoperatively was not significant between the cohorts (P = .09). Preoperative strength measures were similar and showed no significance between cohorts.

Intraoperative analysis Range of motion was analysed intraoperatively, with the patients under anaesthesia. The mean external rotation was reduced in the first cohort with the shorter duration of symptoms at 17° ± 17° compared to 27° ± 27° in the second cohort and found to be significant (P = .03). The same pattern is observed in all other planes of motion and showed the cohort with the shorter duration of symptoms to be more restricted before surgery. The mean internal rotation was significantly less in the shorter symptoms cohort than the longer symptoms cohort, at S3 ± 3 vs. S1 ± 4, respectively; (P =.03).

z3432211 – Ahmed Jamal Harisha Intraoperative abduction in the first cohort was 78° ± 30°, compared to 92° ± 39° in the second cohort; (P = .04). Likewise, forward flexion was more restricted in the first cohort than the second cohort but not significant; 88° ± 28° vs. 101° ± 38° respectively; (P = .06).

Postoperative analysis Both cohorts demonstrated improvements in range of motion and strength at 1 week, 6 weeks, 12 weeks, 24 weeks and six months’ post-surgery. The change from preoperative to six months’ post-operative range of motion was also measured and tabulated. External rotation showed a slight improvement in the first cohort compared to the second cohort, but not significant; 31° ± 25° vs. 20° ± 35° respectively, (P = .23), (Fig. 1).

** = P < 0.01 between cohorts * = P < 0.05 between cohorts


Figure 1 – External rotation measured preoperatively, intraoperatively and the change from preoperative to six months’ after surgery in the shorter symptoms and longer symptoms cohort.

The mean internal rotation in the shorter symptoms cohort was markedly improved from S2 ± 4, preoperatively to T11 ± 5 vertebral levels, six months’ post-operatively, compared to from S2 ± 4 to L2 ± 6 in the longer symptoms cohort, (P = .02), (Fig. 2).

* = P < 0.05 between cohorts

Figure 2 - Internal rotation measured preoperatively, intraoperatively and the change from preoperative to six months’ after surgery in the shorter symptoms and longer symptoms cohort. (For the y axis ((0 = S5 up to 9 = L1)). The change in preoperative to six months’ after surgery was measured in number of levels and doesn’t represent a certain level.

Forward flexion and abduction showed the same pattern, improving more in the shorter symptoms cohort compared to the longer symptoms cohort; 58° ± 38° vs. 49° ± 37°, and, 62° ± 45° vs. 52° ± 49° respectively. External rotation strength in the shorter

z3432211 – Ahmed Jamal Harisha symptoms cohort was higher

than the longer symptoms

cohort at 6 weeks

postoperatively and found to be significant, 43 ± 19 vs. 33 ± 17; (P = .01). Adduction strength at 6 weeks’ post-surgery continued this trend, 61 ± 25 vs. 47 ± 23; (P = .01). Patient-ranked stiffness and overall shoulder satisfaction demonstrated no significa nc e between cohorts; (P = .63), (P = .45) respectively. Table 1 provides a list of the significant results.

TABLE 1 Comparison of Significant Results in the Shorter Symptoms Cohort vs. the Longer Symptoms Cohort 

 Values are expressed as mean ± standard deviation.

Correlation Tables A correlation analysis demonstrated the list of variables that showed a significa nt correlation with the change in external rotation from preoperatively to six months’ postoperatively. The variables with the strongest correlation to this were preoperative external rotation (r = 0.58, P < .0001), preoperative forward flexion (r – 0.28, P = .006),

z3432211 – Ahmed Jamal Harisha preoperative abduction (r = 0.25, P = .025), age at surgery (r = 0.24, P = .024) and sex (male), (r = 0.2, P = .05) (Table 2). Factors that did not display a statistically significa nt correlation with the change in external rotation included side affected (P = .14), operative time (P = .28), duration of symptoms (P = .5), preoperative internal rotation (P = .8) and capsular release vs. manipulation under anaesthesia (P = .89).

TABLE 2 Variables Significantly Correlated with the Change in External Rotation from Pre-Operatively to Six Months Post-Operatively** **The measured preoperative variables (* denotes the measurement of observation was made

Variable

Absolute

Correlation Direction

of P Value

(r)

Correlation

External Rotation*

0.58

Negative