Plantar fasciitis: Clinical concerns in basketball
Sponsored by an educational grant from Medi USA.
Basketball is associated with a high number of lower extremity injuries,1,2 often related to footwear and the unique biomechanics and repetitious motion of the sport. This reflects the evolution of basketball from a refined sport to one of extreme physical contact and leverage. At elite levels of competition, the joint loading that comes with players’ size also contributes to lower extremity injury risk; large players with large feet frequently have large problems.
The mainstream media has given considerable attention to the loss of playing time associated with plantar fasciitis in highly compensated athletes, but recreational players also present a challenge to sports medicine clinics. As many as 45.9% of players in Australia have been sidelined for more than a week with lower extremity injuries.3
The plantar “fascia” is not actually fascia but an aponeurosis with mechanical and histological similarities to surrounding tendons and ligaments.4 Plantar heel pain is one of the most common ailments in the US, accounting for up to two million annual visits to physicians and comprising up to 10% of all sports clinic visits.5,6 It presents with pain with the first step in the morning or after prolonged bouts of sitting.
Repetitive stress can inflame the plantar fascia or lead to degenerative changes, commonly called fasciosis, which explains the recalcitrant nature of the condition. Altered hydrostatic pressure in the fascia may also impede blood flow.7
Plantar fasciitis in basketball players
Although there is a shortage of information about the incidence of plantar fasciitis in basketball players, plantar fascia rupture associated with basketball has been reported.8 Factors contributing to the high incidence of lower extremity and foot and ankle injuries in basketball, and more specifically to plantar fasciitis, include the repetitive high loads associated with running,9 as well as jumping, landing, and cutting by players who often are large in frame.1,2 Other factors that may contribute to plantar fasciitis risk in basketball include footwear and fatigue.
Body mass index (BMI). Van Leeuwen et al found a positive association between patients with a high BMI and plantar fasciitis.10BMI was the only variable that predicted disability in an earlier study.11
The average National Basketball Association (NBA) player weighs 220 lbs and wears a size 14.8 shoe, maxing out at size 20.12 Higher BMI theoretically causes increased vertical force during heel contact, with a concomitant increase in tissue stress.13 However, reduction of body weight and lower extremity anthropometrics typically is not feasible for the basketball player.
Plantar loads. Although no studies have examined the association between plantar loads and plantar fasciitis in basketball players, evidence does suggest that runners with plantar fasciitis have higher plantar loads and loading rates than healthy runners.9 Because much of basketball involves running—not to mention changes of direction, jumping, and landing on hard and unyielding court surfaces—it seems likely that plantar loads in basketball are at least as high as in running.
Basketball movements other than running have also been associated with high loads. Cutting movements, which are common in basketball, have been associated with high plantar pressures at the heel in other sports.14 Layups, free throws, and jump shots are all associated with greater plantar loads than static stance.15 Ground reaction forces (GRF) associated with jump shots in basketball have been reported to be more than five times body weight, heightening the risk of damage with repetition.16 In fact, ground reaction forces are higher in basketball players than soccer players.17 Learning how to land softly and on the forefoot or midfoot will reduce landing GRF;16 however, this is an adjustment that recreational players may not have mastered.
Running volume. There is some evidence that plantar fasciitis may be associated with a faster running pace.18 Basketball involves high acceleration and anaerobic bursts of running. Highly effective basketball players may run up and down a 90-foot court at high speed a minimum of 50 times per game, resulting in increased strain on the intrinsic muscles of the foot.19
Basketball shoes. The most coveted basketball shoes have transitioned from being highly structured to being lightweight and flexible. At the most elite levels, basketball players are restricted in their choice of shoes due to footwear contracts. Colleges often use basketball shoe brands as a tool in recruiting high school players.20
Most important, the shoe must be able to withstand high plantar loading without deformation and resist the rotational and cutting forces that stretch the upper in a very moist environment. Frequent footwear changes can help reduce midsole fatigue. Shoes have been shown to reduce impact forces during unanticipated drop landings in basketball.21
For many basketball players, the shoe is not wide enough, especially with added bulk of high-profile orthoses.22 If the shoe doesn’t have sufficient volume to allow for proper activation of muscles (eg, abductor hallucis), this can impair the propulsive function of the longitudinal arch during walking and running.19,23
Lower extremity clinicians who treat basketball players say the game has changed since the late 1990s from one played close to the basket to one played around the perimeter. This switch requires more lateral footwork, with more stresses to the ankle and plantar fascia. In response, basketball shoe designs have evolved to reinforce the lateral border to reduce ankle sprains and promote quicker directional changes. This design shift has led to shoes with reduced medial support and amplified pronatory moments, which may increase the risk of plantar fasciitis.
There also has been a transition to lightweight shoes. Interestingly, a group of researchers in Calgary found that lighter-weight shoes were associated with improved performance of basketball tasks, but not when athletes were blinded to the weight of the shoes, suggesting a psychological effect.24 There is a need for further research on the functional effects of lighter footwear, including foot orthoses.
Sport-specific factors. Although basketball originated as a noncontact sport, its physical nature has evolved over the years with regard to both offense and defense.25 Rapid braking and acceleration (vertical and horizontal), along with lateral shifts of body weight, are very demanding on the foot and ankle.
Steve Vinson, who coaches girls basketball at Ann Arbor Huron High School in Michigan, said plantar fasciitis in younger athletes is a growing concern, with competition for scholarships leading to more aggressive play, and intense schedules leaving little time to recuperate from the stresses associated with the sport.26
Treatment and prevention
The treatment paradigm of rest, cessation of activity, or both is often not feasible for high-level athletes. Changes in jumping technique, which can help reduce the risk of knee and ankle injuries,16,27 have not been studied in cases of plantar fasciitis or fasciopathy. Taylor stressed prevention and proprioception programs to reduce the incidence of ankle sprains and lower extremity injuries, but there has been no attempt to study or adapt these programs for the prevention of plantar fasciitis.27
Plantar fascia corticosteroid injections in athletes may have unintended adverse effects, with some accounts of rupture after early re-entry into play.28 Additionally, surgical management with plantar fasciotomy has only moderately improved patient outcomes in the general population, often resulting in extended recovery time.29,30 The risks of adverse events must be weighed judiciously in any treatment paradigm.
An orthotic device with intrinsic or extrinsic medial wedges was associated with greater soft tissue thickness under the heel, which may protect the fat pad (assessed statically) more than no orthosis or an orthosis with arch support only.31 This may have implications for treatment of plantar fasciitis given the condition’s association with fat pad atrophy in some patients.32 Further investigation is warranted.
The diagonal cuts and lateral shuffle cuts in basketball are also associated with elevated forces under the metatarsal heads.33,34Plantar fasciitis interventions to redistribute plantar pressures must take care to avoid overloading the metatarsals.35,36
Treatment must mitigate deleterious forces on the foot with the following orthotic strategies. Orthoses must:
Reduce impact plantar loading without inhibiting performance or excessively increasing load in other areas; accommodative or shock-absorbing inserts are much better tolerated by basketball players;22,37
Not elevate the heel or destabilize the ankle;7
Not hamper the function of the abductor hallucis and intrinsic muscles;
Have reduced arch height to minimize pressure shift laterally and decrease fifth metatarsal head pressure;31 and
Not impede blood flow to the foot from excessive pressure.38
Plantar fasciitis in basketball will continue to be a growing concern made even more clinically challenging by the lack of specific research on foot and ankle biomechanics in this popular and strenuous sport. Vigilant clinical judgment, informed by the broader body of research on the biomechanics of plantar fasciitis, will be essential to meeting this challenge.
Patricia Pande, MClScPT, CSCS, CPed, is a physical therapist, pedorthist, and strength and conditioning specialist based in Durham, NC. She is the founder of FootCentric, an online continuing education company dedicated to comprehensive, multidisciplinary foot treatment.