The Effects of Spinal Mobilization Added to an Exercise Program in Recreational Tennis Players With Mechanical Low Back Pain

The Effects of Spinal Mobilization Added to an Exercise Program on Pain and Physical Fitness in Recreational Tennis Players With Mechanical Low Back Pain

This prospective, single-blind, randomized controlled trial investigates whether the addition of spinal mobilization to a structured home exercise program improves pain, flexibility, lower-extremity strength, dynamic balance, and jump performance in recreational tennis players (aged 18-45 years; BMI 18-30 kg/m²) with non-radiating mechanical low back pain. Participants were allocated to two parallel groups: a Control Group performing a 21-session home exercise program for 3 weeks, and an Experimental Group performing the same program plus four physiotherapist-administered spinal mobilization sessions (one at baseline and one weekly for 3 weeks). Outcomes were the Visual Analog Scale (VAS) for pain during physical activity, at rest, and at night; the Y-Balance Test; the Vertical Jump Test; the Sit-and-Reach Test; and isometric strength measured with a back-chest-leg dynamometer.

Design: prospective, randomized, single-blind, parallel-group controlled clinical trial. The study was conducted under the supervision of the Department of Physiotherapy and Rehabilitation, Chiropractic Master's Program. Recreational tennis players (aged 18-45 years; BMI 18-30 kg/m²) with mechanical low back pain of more than 1 week duration and a baseline pain intensity exceeding 4 on the Visual Analog Scale (VAS) who played tennis at least twice per week (≥2 hours/week) were enrolled after providing written informed consent. Allocation was performed using sealed opaque envelopes combined with computer-assisted randomization, with masking applied to the outcome assessor. Participants were randomized to: (1) Control Group (CG) - structured home exercise program comprising posterior pelvic tilt, erector spinae stretching (double knee-to-chest), combined hamstring/lumbar extensor stretching (long-sit toe touch), piriformis stretching, and static hamstring stretching (5 repetitions of 30-second holds for stretches; 5 repetitions of 10-second holds for posterior pelvic tilt); the program was performed daily for 21 sessions over 3 weeks and supported by written instructions, visual materials, and weekly telephone follow-up; (2) Experimental Group (EG) - the identical home exercise program plus four sessions of supervised spinal mobilization delivered by a physiotherapist (one at baseline and once weekly for 3 weeks). Mobilization was administered according to the Maitland classification (graded I to V; end-range was not forced) and included thoracic posteroanterior mobilization (T5-T12), rotational thoracic mobilization ("butterfly/screw" technique), sacroiliac mobilization, side-lying lumbar mobilization, and anteroposterior lumbar mobilization. Each technique was applied as five sets of one-minute oscillations with 20-second rest intervals across the posteroanterior, mediolateral, and transverse planes. Outcome assessments were performed at baseline (Week 0) and at the end of the intervention (Week 3) by a single blinded assessor. Pain was quantified with three 10-cm Visual Analog Scales (physical activity, rest, and night). Dynamic balance was assessed with the Y-Balance Test in three directions (anterior, posteromedial, posterolateral). Lower-extremity power was measured with the Vertical Jump Test using the validated My Jump Lab application (iPhone 15 Pro Max). Hamstring and lumbar flexibility were measured with a Baseline sit-and-reach box. Isometric strength of the back, chest, and leg extensors was measured with a calibrated Baseline back-chest-leg dynamometer (New York, USA). Statistical plan: normality was tested by Shapiro-Wilk; within-group changes were analysed by paired-samples t-test, between-group differences by independent-samples t-test, and categorical variables by Chi-square; Cohen's d was calculated for parameters with significant within-group changes. Analyses were performed in IBM SPSS 25.0. A priori sample size estimation (G*Power 3.1.9.2) with 85% power, an effect size of d = 0.8, and α = 0.05 yielded a target of 30 participants; 32 were enrolled to allow for attrition. Post hoc power analysis based on the post-intervention VAS during physical activity (d = 1.24, α = 0.05) yielded a power of 0.91. No external funding; no conflicts of interest declared.

Inclusion Criteria:

• Adults aged 18-45 years.
• Body mass index (BMI) between 18 and 30 kg/m².
• Mechanical low back pain that decreases in the supine position and increases with activity or in various postures.
• Low back pain of more than one week duration with a baseline intensity greater than 4 on the Visual Analog Scale (VAS) and unrelated to any defined medical condition.
• Playing tennis on a recreational basis at least 2 days per week, totalling at least 2 hours per week.
• Able to communicate in Turkish or English in both written and spoken form.

Exclusion Criteria:

• Pain in the lower back, hip, or groin lasting longer than 6 months.
• Pain accompanied by a sensory deficit.
• Pain radiating to the hip or lower extremity.
• History of long-term steroid use.
• Regular medication use.
• History of injury or surgery resulting in residual deficits.
• Previous interventional treatment to the lumbar region.
• Pregnancy or suspected pregnancy.

Termination Criteria During Study:

• Onset of an acute illness requiring treatment (e.g., influenza, pneumonia).
• Use of analgesic or sedative medication.
• An increase in VAS pain score greater than 3 points during exercise or treatment.
• Failure to perform the home exercise programme on three consecutive days.
• Missed manual therapy session.